diff --git a/scripts/increment-cargo-version.sh b/scripts/increment-cargo-version.sh
index dae455b1a..6c5872130 100755
--- a/scripts/increment-cargo-version.sh
+++ b/scripts/increment-cargo-version.sh
@@ -58,7 +58,7 @@ major)
 minor)
   MINOR=$((MINOR+ 1))
   ;;
--*)
+-[A-Za-z0-9]*$)
   SPECIAL="$1"
   ;;
 *)