Index: Jenkins/tools.groovy
===================================================================
--- Jenkins/tools.groovy	(revision 6c9e0bc4fcb6f530280212e572b29daed0350875)
+++ Jenkins/tools.groovy	(revision 6a531abe77c465b5c3cafd6981a444ef24586410)
@@ -61,5 +61,13 @@
 }
 
-def GitLogMessage(String oldRef, String newRef) {
+PrevGitOldRef = ''
+PrevGitNewRef = ''
+def GitLogMessage(String oldRef = '', String newRef = '') {
+	if (!PrevGitOldRef || !oldRef) return "\nERROR retrieveing git information!\n"
+	PrevGitOldRef = oldRef
+
+	if (!PrevGitNewRef || !newRef) return "\nERROR retrieveing git information!\n"
+	PrevGitNewRef = newRef
+
 	def revText = sh(returnStdout: true, script: "git rev-list ${oldRef}..${newRef}").trim()
 	def revList = SplitLines( revText )