diff --git a/src/libCom/osi/devLib.c b/src/libCom/osi/devLib.c
index 6e2f44bbd..6a8aa68e6 100644
--- a/src/libCom/osi/devLib.c
+++ b/src/libCom/osi/devLib.c
@@ -941,6 +941,20 @@ void			(*pFunction)(void *) )
     return (*pdevLibVirtualOS->pDevDisconnectInterruptVME) (vectorNumber, pFunction);
 }
 
+int devInterruptInUseVME (unsigned level)
+{
+    long status;
+
+    if (!devLibInitFlag) {
+        status = devLibInit();
+        if (status) {
+            return status;
+        }
+    }
+
+    return (*pdevLibVirtualOS->pDevInterruptInUseVME) (level);
+}
+
 long devEnableInterruptLevelVME (unsigned level)
 {
     long status;
diff --git a/src/libCom/osi/devLib.h b/src/libCom/osi/devLib.h
index f9dd85751..2cd2471e8 100644
--- a/src/libCom/osi/devLib.h
+++ b/src/libCom/osi/devLib.h
@@ -330,6 +330,11 @@ typedef struct devLibVirtualOS {
         void *(*pDevA24Malloc)(size_t nbytes);
         void (*pDevA24Free)(void *pBlock);
         long (*pDevInit)(void);
+
+	/*
+	 * test if VME interrupt has an ISR connected
+	 */
+	int (*pDevInterruptInUseVME) (unsigned vectorNumber);
 }devLibVirtualOS;
 epicsShareExtern devLibVirtualOS *pdevLibVirtualOS;
 
diff --git a/src/libCom/osi/os/RTEMS/devLibOSD.c b/src/libCom/osi/os/RTEMS/devLibOSD.c
index 5f8ceb9ad..50f1ffe36 100644
--- a/src/libCom/osi/os/RTEMS/devLibOSD.c
+++ b/src/libCom/osi/os/RTEMS/devLibOSD.c
@@ -101,6 +101,8 @@ static long rtmsDevEnableInterruptLevelVME (unsigned level);
 
 static long rtmsDevDisableInterruptLevelVME (unsigned level);
 
+static int rtemsDevInterruptInUseVME (unsigned vectorNumber);
+
 /* RTEMS specific init */
 
 /*devA24Malloc and devA24Free are not implemented*/
@@ -115,7 +117,7 @@ static devLibVirtualOS rtemsVirtualOS = {
     rtmsDevMapAddr, rtmsDevReadProbe, rtmsDevWriteProbe, 
     rtmsDevConnectInterruptVME, rtmsDevDisconnectInterruptVME,
     rtmsDevEnableInterruptLevelVME, rtmsDevDisableInterruptLevelVME,
-    devA24Malloc,devA24Free,rtmsDevInit
+    devA24Malloc,devA24Free,rtmsDevInit,rtemsDevInterruptInUseVME
 };
 devLibVirtualOS *pdevLibVirtualOS = &rtemsVirtualOS;
 
@@ -296,7 +298,7 @@ static myISR *isrFetch(unsigned vectorNumber, void **parg)
 /*
  * determine if a VME interrupt vector is in use
  */
-int devInterruptInUseVME (unsigned vectorNumber)
+static int rtemsDevInterruptInUseVME (unsigned vectorNumber)
 {
     int i;
     myISR *psub;
diff --git a/src/libCom/osi/os/vxWorks/devLibOSD.c b/src/libCom/osi/os/vxWorks/devLibOSD.c
index 28a32c660..ca95b3b60 100644
--- a/src/libCom/osi/os/vxWorks/devLibOSD.c
+++ b/src/libCom/osi/os/vxWorks/devLibOSD.c
@@ -128,6 +128,8 @@ static long vxDevEnableInterruptLevelVME (unsigned level);
 
 static long vxDevDisableInterruptLevelVME (unsigned level);
 
+static int vxDevInterruptInUseVME (unsigned vectorNumber);
+
 /*
  * used by dynamic bind in devLib.c
  */
@@ -135,7 +137,7 @@ static devLibVirtualOS vxVirtualOS = {
     vxDevMapAddr, vxDevReadProbe, vxDevWriteProbe, 
     vxDevConnectInterruptVME, vxDevDisconnectInterruptVME,
     vxDevEnableInterruptLevelVME, vxDevDisableInterruptLevelVME,
-    devA24Malloc,devA24Free,devInit
+    devA24Malloc,devA24Free,devInit,vxDevInterruptInUseVME
 };
 devLibVirtualOS *pdevLibVirtualOS = &vxVirtualOS;
 
@@ -373,7 +375,7 @@ static myISR *isrFetch(unsigned vectorNumber)
 /*
  * determine if a VME interrupt vector is in use
  */
-int devInterruptInUseVME (unsigned vectorNumber)
+static int vxDevInterruptInUseVME (unsigned vectorNumber)
 {
 #if CPU_FAMILY == PPC
     return FALSE;