diff --git a/modules/libcom/src/osi/os/vxWorks/osdThread.h b/modules/libcom/src/osi/os/vxWorks/osdThread.h
index 32d7dbd64..09ecbb553 100644
--- a/modules/libcom/src/osi/os/vxWorks/osdThread.h
+++ b/modules/libcom/src/osi/os/vxWorks/osdThread.h
@@ -13,8 +13,18 @@
 
 /* VxWorks 6.9 and later can support joining threads */
 
-#if (!defined(_WRS_VXWORKS_MAJOR) || _WRS_VXWORKS_MAJOR == 6 && _WRS_VXWORKS_MINOR < 9)
-#undef EPICS_THREAD_CAN_JOIN
+#include <epicsVersion.h>
+
+#ifdef _WRS_VXWORKS_MAJOR
+#define VXWORKS_VERSION_INT VERSION_INT(_WRS_VXWORKS_MAJOR, \
+    _WRS_VXWORKS_MINOR, _WRS_VXWORKS_MAINT, _WRS_VXWORKS_SVCPK)
+#else
+/* Version not available at compile-time, assume... */
+#define VXWORKS_VERSION_INT VERSION_INT(5, 5, 0, 0)
+#endif
+
+#if VXWORKS_VERSION_INT < VERSION_INT(6, 9, 4, 1)
+# undef EPICS_THREAD_CAN_JOIN
 #endif
 
 #endif /* osdThreadh */