diff --git a/src/ca/nciu.cpp b/src/ca/nciu.cpp
index dda1d4201..ba08015b4 100644
--- a/src/ca/nciu.cpp
+++ b/src/ca/nciu.cpp
@@ -413,6 +413,12 @@ unsigned nciu::getHostName (
         guard, pBuf, bufLength );
 }
 
+const char * nciu::pHostName (
+    epicsGuard < epicsMutex > & guard ) const throw ()
+{
+    return this->piiu->pHostName ( guard );
+}
+
 bool nciu::ca_v42_ok (
     epicsGuard < epicsMutex > & guard ) const
 {
diff --git a/src/ca/nciu.h b/src/ca/nciu.h
index adba67457..0890d6b89 100644
--- a/src/ca/nciu.h
+++ b/src/ca/nciu.h
@@ -262,8 +262,10 @@ private:
     arrayElementCount nativeElementCount (
         epicsGuard < epicsMutex > & ) const;
     static void stringVerify ( const char *pStr, const unsigned count );
-    virtual void ioCompletionNotify ( 
+    void ioCompletionNotify ( 
         epicsGuard < epicsMutex > &, class baseNMIU & );
+    const char * pHostName (
+        epicsGuard < epicsMutex > & guard ) const throw ();
 	nciu ( const nciu & );
 	nciu & operator = ( const nciu & );
     void * operator new ( size_t );
diff --git a/src/ca/netiiu.cpp b/src/ca/netiiu.cpp
index f8e4883cd..fce19764d 100644
--- a/src/ca/netiiu.cpp
+++ b/src/ca/netiiu.cpp
@@ -110,7 +110,7 @@ unsigned netiiu::getHostName (
 }
 
 const char * netiiu::pHostName (
-    epicsGuard < epicsMutex > & ) const
+    epicsGuard < epicsMutex > & ) const throw ()
 {
     return pHostNameNetIIU;
 }
diff --git a/src/ca/netiiu.h b/src/ca/netiiu.h
index 286f06058..a6f1c36fe 100644
--- a/src/ca/netiiu.h
+++ b/src/ca/netiiu.h
@@ -42,7 +42,7 @@ public:
         epicsGuard < epicsMutex > &, char * pBuf, 
         unsigned bufLength ) const throw () = 0;
     virtual const char * pHostName (
-        epicsGuard < epicsMutex > & ) const = 0;
+        epicsGuard < epicsMutex > & ) const throw () = 0;
     virtual bool ca_v41_ok (
         epicsGuard < epicsMutex > & ) const = 0;
     virtual bool ca_v42_ok (
diff --git a/src/ca/noopiiu.cpp b/src/ca/noopiiu.cpp
index 0a7dcd485..86aeaca0e 100644
--- a/src/ca/noopiiu.cpp
+++ b/src/ca/noopiiu.cpp
@@ -41,7 +41,7 @@ unsigned noopiiu::getHostName (
 }
 
 const char * noopiiu::pHostName (
-    epicsGuard < epicsMutex > & cacGuard ) const
+    epicsGuard < epicsMutex > & cacGuard ) const throw ()
 {
     return netiiu::pHostName ( cacGuard );
 }
diff --git a/src/ca/noopiiu.h b/src/ca/noopiiu.h
index 58099b9f9..7a5b6f11c 100644
--- a/src/ca/noopiiu.h
+++ b/src/ca/noopiiu.h
@@ -34,7 +34,7 @@ public:
         epicsGuard < epicsMutex > &, char * pBuf, 
         unsigned bufLength ) const throw ();
     const char * pHostName (
-        epicsGuard < epicsMutex > & ) const; 
+        epicsGuard < epicsMutex > & ) const throw (); 
     bool ca_v41_ok (
         epicsGuard < epicsMutex > & ) const;
     bool ca_v42_ok (
diff --git a/src/ca/tcpiiu.cpp b/src/ca/tcpiiu.cpp
index d942ea455..b3109cfe9 100644
--- a/src/ca/tcpiiu.cpp
+++ b/src/ca/tcpiiu.cpp
@@ -1708,7 +1708,7 @@ unsigned tcpiiu::getHostName (
 }
 
 const char * tcpiiu::pHostName (
-    epicsGuard < epicsMutex > & guard ) const
+    epicsGuard < epicsMutex > & guard ) const throw ()
 {
     guard.assertIdenticalMutex ( this->mutex );
     return this->hostNameCacheInstance.pointer ();
diff --git a/src/ca/udpiiu.cpp b/src/ca/udpiiu.cpp
index e74264328..22e5525cf 100644
--- a/src/ca/udpiiu.cpp
+++ b/src/ca/udpiiu.cpp
@@ -1135,7 +1135,7 @@ unsigned udpiiu::getHostName (
 }
 
 const char * udpiiu::pHostName (
-    epicsGuard < epicsMutex > & cacGuard ) const
+    epicsGuard < epicsMutex > & cacGuard ) const throw ()
 {
     return netiiu::pHostName ( cacGuard );
 }
diff --git a/src/ca/udpiiu.h b/src/ca/udpiiu.h
index 94cf9b7df..aa5256efd 100644
--- a/src/ca/udpiiu.h
+++ b/src/ca/udpiiu.h
@@ -181,7 +181,7 @@ private:
         epicsGuard < epicsMutex > &, char * pBuf, 
         unsigned bufLength ) const throw ();
     const char * pHostName (
-        epicsGuard < epicsMutex > & ) const; 
+        epicsGuard < epicsMutex > & ) const throw (); 
         bool ca_v41_ok (
         epicsGuard < epicsMutex > & ) const;
     bool ca_v42_ok (
diff --git a/src/ca/virtualCircuit.h b/src/ca/virtualCircuit.h
index daaf31fa6..dfcb6797f 100644
--- a/src/ca/virtualCircuit.h
+++ b/src/ca/virtualCircuit.h
@@ -242,7 +242,7 @@ private:
     void recvBytes ( 
         void * pBuf, unsigned nBytesInBuf, statusWireIO & );
     const char * pHostName (
-        epicsGuard < epicsMutex > & ) const;
+        epicsGuard < epicsMutex > & ) const throw ();
     double receiveWatchdogDelay (
         epicsGuard < epicsMutex > & ) const;
     void unresponsiveCircuitNotify (