diff --git a/config/CONFIG.Host.solaris b/config/CONFIG.Host.solaris
index 53d3a1572..ca0ebd501 100644
--- a/config/CONFIG.Host.solaris
+++ b/config/CONFIG.Host.solaris
@@ -67,7 +67,7 @@ CCC_SHRLIB_CFLAGS_YES =
 CCC_SHRLIB_LDFLAGS_YES =  -G -h $@ -z ignore -z combreloc -z lazyload
  
 
-ARCH_DEP_CFLAGS = -DSOLARIS
+ARCH_DEP_CFLAGS = -DSOLARIS=$(subst 5.,,$(shell uname -r)) 
 POSIX_CPPFLAGS_YES += -D__EXTENSIONS__
 
 # socket and nsl needed by libca.a
diff --git a/config/CONFIG.Host.solaris-x86 b/config/CONFIG.Host.solaris-x86
index 9376db31e..5d1ce5ece 100644
--- a/config/CONFIG.Host.solaris-x86
+++ b/config/CONFIG.Host.solaris-x86
@@ -15,7 +15,8 @@
 -include $(EPICS_BASE)/config/CONFIG.Host.solaris
 
 # Solaris on x86
-ARCH_DEP_CFLAGS = -DSOLARIS  -D_X86_ -D__EXTENSIONS__
+ARCH_DEP_CFLAGS = -DSOLARIS=$(subst 5.,,$(shell uname -r))  -D_X86_  -D__EXTENSIONS__
 
 GCC = gcc
 G++ = g++
+