diff --git a/include/Main.awk b/include/Main.awk
index 69a06139..d66add4c 100644
--- a/include/Main.awk
+++ b/include/Main.awk
@@ -755,7 +755,7 @@ BEGIN {
 
         # Shortcut format
         # 'CODE:CODE+...' or 'CODE=CODE+...'
-        match(ARGV[pos], /^[{(\[]?((@?[[:alpha:]][[:alpha:]][[:alpha:]]?(-[[:alpha:]][[:alpha:]][[:alpha:]]?[[:alpha:]]?)?\+)*(@?[[:alpha:]][[:alpha:]][[:alpha:]]?(-[[:alpha:]][[:alpha:]][[:alpha:]]?[[:alpha:]]?)?)?)?(:|=)((@?[[:alpha:]][[:alpha:]][[:alpha:]]?(-[[:alpha:]][[:alpha:]][[:alpha:]]?[[:alpha:]]?)?\+)*(@?[[:alpha:]][[:alpha:]][[:alpha:]]?(-[[:alpha:]][[:alpha:]][[:alpha:]]?[[:alpha:]]?)?)?)[})\]]?$/, group)
+        match(ARGV[pos], /^[{(\[]?((@?[a-z][a-z][a-z]?(-[[:alpha:]][[:alpha:]][[:alpha:]]?[[:alpha:]]?)?\+)*(@?[a-z][a-z][a-z]?(-[[:alpha:]][[:alpha:]][[:alpha:]]?[[:alpha:]]?)?)?)?(:|=)((@?[a-z][a-z][a-z]?(-[[:alpha:]][[:alpha:]][[:alpha:]]?[[:alpha:]]?)?\+)*(@?[a-z][a-z][a-z]?(-[[:alpha:]][[:alpha:]][[:alpha:]]?[[:alpha:]]?)?)?)[})\]]?$/, group)
         if (RSTART) {
             if (group[1]) {
                 split(group[1], Option["sls"], "+")