diff --git a/src/ca/CASG.cpp b/src/ca/CASG.cpp
index a2fd6dce5..003102a3a 100644
--- a/src/ca/CASG.cpp
+++ b/src/ca/CASG.cpp
@@ -31,6 +31,7 @@
 #include "oldAccess.h"
 
 tsFreeList < struct CASG, 128 > CASG::freeList;
+epicsMutex CASG::freeListMutex;
 
 CASG::CASG (cac &cacIn) :
     client (cacIn), magic (CASG_MAGIC), opPendCount (0u), seqNo (0u)
@@ -46,13 +47,14 @@ void CASG::destroy ()
 CASG::~CASG ()
 {
     if ( this->verify () ) {
-        this->mutex.lock ();
-        tsDLIterBD <syncGroupNotify> notify = this->ioList.firstIter ();
-        while ( notify.valid () ) {
-            notify->release ();
-            notify = this->ioList.firstIter ();
+        {
+            epicsAutoMutex locker ( this->mutex );
+            tsDLIterBD <syncGroupNotify> notify = this->ioList.firstIter ();
+            while ( notify.valid () ) {
+                notify->release ();
+                notify = this->ioList.firstIter ();
+            }
         }
-        this->mutex.unlock ();
         this->client.uninstallCASG ( *this );
         this->magic = 0;
     }
@@ -82,16 +84,6 @@ int CASG::block ( double timeout )
         return ECA_TIMEOUT;
     }
 
-    /*
-     * dont allow recursion
-     */
-    void *p = epicsThreadPrivateGet ( cacRecursionLock );
-    if ( p ) {
-        return ECA_EVDISALLOW;
-    }
-
-    epicsThreadPrivateSet ( cacRecursionLock, &cacRecursionLock );
-
     cur_time = epicsTime::getCurrent ();
 
     this->client.flush ();
@@ -103,17 +95,16 @@ int CASG::block ( double timeout )
 
     status = ECA_NORMAL;
     while ( 1 ) {
-        this->mutex.lock ();
-        if ( this->seqNo != initialSeqNo ) {
-            this->mutex.unlock ();
-            break;
+        {
+            epicsAutoMutex locker ( this->mutex );
+            if ( this->seqNo != initialSeqNo ) {
+                break;
+            }
+            if ( this->opPendCount == 0u ) {
+                this->seqNo++;
+                break;
+            }
         }
-        if ( this->opPendCount == 0u ) {
-            this->seqNo++;
-            this->mutex.unlock ();
-            break;
-        }
-        this->mutex.unlock ();
 
         remaining = timeout - delay;
         if ( remaining <= CAC_SIGNIFICANT_SELECT_DELAY ) {
@@ -122,9 +113,10 @@ int CASG::block ( double timeout )
              * recv backlog at least once
              */
             status = ECA_TIMEOUT;
-            this->mutex.lock ();
-            this->seqNo++;
-            this->mutex.unlock ();
+            {
+                epicsAutoMutex locker ( this->mutex );
+                this->seqNo++;
+            }
             break;
         }
 
@@ -140,32 +132,28 @@ int CASG::block ( double timeout )
 
     this->client.disableCallbackPreemption ();
 
-    epicsThreadPrivateSet (cacRecursionLock, NULL);
-
     return status;
 }
 
 void CASG::reset ()
 {
-    this->mutex.lock ();
+    epicsAutoMutex locker ( this->mutex );
     this->opPendCount = 0;
     this->seqNo++;
-    this->mutex.unlock ();
 }
 
 void CASG::show ( unsigned level) const
 {
-    printf ("Sync Group: id=%u, magic=%u, opPend=%lu, seqNo=%lu\n",
-        this->getId (), this->magic, this->opPendCount, this->seqNo);
+    printf ( "Sync Group: id=%u, magic=%u, opPend=%lu, seqNo=%lu\n",
+        this->getId (), this->magic, this->opPendCount, this->seqNo );
 
     if ( level ) {
-        this->mutex.lock ();
-        tsDLIterConstBD <syncGroupNotify> notify = this->ioList.firstIter ();
+        epicsAutoMutex locker ( this->mutex );
+        tsDLIterConstBD < syncGroupNotify > notify = this->ioList.firstIter ();
         while ( notify.valid () ) {
             notify->show (level);
             notify++;
         }
-        this->mutex.unlock ();
     }
 }
 
@@ -176,11 +164,13 @@ bool CASG::ioComplete () const
 
 void * CASG::operator new (size_t size)
 {
+    epicsAutoMutex locker ( CASG::freeListMutex );
     return CASG::freeList.allocate ( size );
 }
 
 void CASG::operator delete (void *pCadaver, size_t size)
 {
+    epicsAutoMutex locker ( CASG::freeListMutex );
     CASG::freeList.release ( pCadaver, size );
 }
 
diff --git a/src/ca/cacServiceList.cpp b/src/ca/cacServiceList.cpp
index a5a125777..5ce0c863e 100644
--- a/src/ca/cacServiceList.cpp
+++ b/src/ca/cacServiceList.cpp
@@ -19,44 +19,37 @@
 
 epicsShareDef cacServiceList cacGlobalServiceList;
 
-cacServiceList::cacServiceList ()
-{
-}
-
 void cacServiceList::registerService ( cacServiceIO &service )
 {
-    this->lock ();
+    epicsAutoMutex locker ( this->mutex );
     this->services.add ( service );
-    this->unlock ();
 }
 
-cacChannelIO * cacServiceList::createChannelIO ( const char *pName, 
-    cac &cacCtx, cacChannelNotify &chan )
+cacChannelIO * cacServiceList::createChannelIO ( 
+    const char *pName, cacChannelNotify &chan )
 {
     cacChannelIO *pChanIO = 0;
 
-    this->lock ();
+    epicsAutoMutex locker ( this->mutex );
     tsDLIterBD < cacServiceIO > iter = this->services.firstIter ();
     while ( iter.valid () ) {
-        pChanIO = iter->createChannelIO ( pName, cacCtx, chan );
+        pChanIO = iter->createChannelIO ( pName, chan );
         if ( pChanIO ) {
             break;
         }
         iter++;
     }
-    this->unlock ();
 
     return pChanIO;
 }
 
 void cacServiceList::show ( unsigned level ) const
 {
-    this->lock ();
+    epicsAutoMutex locker ( this->mutex );
     tsDLIterConstBD < cacServiceIO > iter = this->services.firstIter ();
     while ( iter.valid () ) {
         iter->show ( level );
         iter++;
     }
-    this->unlock ();
 }
 
diff --git a/src/ca/comBuf_IL.h b/src/ca/comBuf_IL.h
index 299bd0934..6096f69bb 100644
--- a/src/ca/comBuf_IL.h
+++ b/src/ca/comBuf_IL.h
@@ -36,11 +36,13 @@ inline void comBuf::destroy ()
 
 inline void * comBuf::operator new ( size_t size )
 {
+    epicsAutoMutex locker ( comBuf::freeListMutex );
     return comBuf::freeList.allocate ( size );
 }
 
 inline void comBuf::operator delete ( void *pCadaver, size_t size )
 {
+    epicsAutoMutex locker ( comBuf::freeListMutex );
     comBuf::freeList.release ( pCadaver, size );
 }
 
@@ -116,7 +118,7 @@ inline unsigned comBuf::removeBytes ( unsigned nBytes )
     return nBytes;
 }
 
-inline unsigned comBuf::maxBytes ()
+inline unsigned comBuf::capacityBytes ()
 {
     return comBufSize;
 }
diff --git a/src/ca/getCallback.cpp b/src/ca/getCallback.cpp
index ae397b64b..026a38364 100644
--- a/src/ca/getCallback.cpp
+++ b/src/ca/getCallback.cpp
@@ -19,6 +19,7 @@
 #include "oldAccess.h"
 
 tsFreeList < class getCallback, 1024 > getCallback::freeList;
+epicsMutex getCallback::freeListMutex;
 
 getCallback::~getCallback ()
 {
diff --git a/src/ca/hostNameCache.cpp b/src/ca/hostNameCache.cpp
index 88250563b..05004578e 100644
--- a/src/ca/hostNameCache.cpp
+++ b/src/ca/hostNameCache.cpp
@@ -17,6 +17,7 @@
 #include "iocinf.h"
 
 tsFreeList < hostNameCache, 16 > hostNameCache::freeList;
+epicsMutex hostNameCache::freeListMutex;
 
 hostNameCache::hostNameCache ( const osiSockAddr &addr, ipAddrToAsciiEngine &engine ) :
     ipAddrToAsciiAsynchronous ( addr ),
diff --git a/src/ca/msgForMultiplyDefinedPV_IL.h b/src/ca/msgForMultiplyDefinedPV_IL.h
index 52da7a12f..e09d3c6ae 100644
--- a/src/ca/msgForMultiplyDefinedPV_IL.h
+++ b/src/ca/msgForMultiplyDefinedPV_IL.h
@@ -17,10 +17,12 @@
 
 void * msgForMultiplyDefinedPV::operator new ( size_t size )
 {
+    epicsAutoMutex locker ( msgForMultiplyDefinedPV::freeListMutex );
     return msgForMultiplyDefinedPV::freeList.allocate ( size );
 }
 
 void msgForMultiplyDefinedPV::operator delete ( void *pCadaver, size_t size )
 {
+    epicsAutoMutex locker ( msgForMultiplyDefinedPV::freeListMutex );
     msgForMultiplyDefinedPV::freeList.release ( pCadaver, size );
 }