diff --git a/debian/rules b/debian/rules
index 88e76abeb..c73a62972 100755
--- a/debian/rules
+++ b/debian/rules
@@ -5,7 +5,7 @@ DEB_HOST_ARCH := $(shell dpkg-architecture -qDEB_HOST_ARCH)
 SOURCE := $(shell dpkg-parsechangelog | sed -ne 's,^Source: *\(.*\)$$,\1,p')
 VERSION := $(shell dpkg-parsechangelog | sed -ne 's,^Version: *\(.*\)$$,\1,p')
 VERSION_UPSTREAM := $(shell echo "$(VERSION)" | sed -e 's,-[^-]*$$,,')
-VERSION_BINNMU := $(shell echo "$(VERSION)" | sed -ne 's,.*\+b\(.*\)$$,\1,p')
+VERSION_BINNMU := $(shell echo "$(VERSION)" | sed -ne 's,.*+b\(.*\)$$,\1,p')
 
 include debian/rules.defs