diff --git a/util/versioncheck.py b/util/versioncheck.py
index 94f5579..dd7e478 100755
--- a/util/versioncheck.py
+++ b/util/versioncheck.py
@@ -8,7 +8,7 @@ version = 'Mininet ' + co( 'PYTHONPATH=. bin/mn --version', shell=True )
 version = version.strip()
 
 # Find all Mininet path references
-lines = co( "egrep -or 'Mininet [0-9\.]+\w*' *", shell=True )
+lines = co( "egrep -or 'Mininet [0-9\.\+]+\w*' *", shell=True )
 
 error = False