diff --git a/src/net/sf/launch4j/config/Jre.java b/src/net/sf/launch4j/config/Jre.java
index cd91661..2de3333 100644
--- a/src/net/sf/launch4j/config/Jre.java
+++ b/src/net/sf/launch4j/config/Jre.java
@@ -54,7 +54,7 @@ public class Jre implements IValidatable {
 	public static final String ARGS = "jvmArgs";
 
 	// __________________________________________________________________________________
-	public static final String VERSION_PATTERN = "(1\\.\\d\\.\\d(_\\d{1,3})?)|[1-9][0-9]{0,2}(\\.\\d{1,3}){0,2}";
+	public static final String VERSION_PATTERN = "(1\\.\\d\\.\\d((_|\\.)\\d{1,3})?)|[1-9][0-9]{0,2}(\\.\\d{1,3}){0,2}";
 	
 	public static final String JDK_PREFERENCE_JRE_ONLY = "jreOnly";
 	public static final String JDK_PREFERENCE_PREFER_JRE = "preferJre";