--- a/buildtools/wafsamba/samba_utils.py	2019-04-08 01:13:47.525306574 +0000
+++ b/buildtools/wafsamba/samba_utils.py	2019-04-08 01:14:34.805245676 +0000
@@ -495,7 +495,7 @@
                 Logs.zones = ['runner']
             if Logs.verbose > 2:
                 Logs.zones = ['*']
-        elif opt[0].isupper() and opt.find('=') != -1:
+        elif opt[0] and opt.find('=') != -1:
             # this allows us to set waf options on the make command line
             # for example, if you do "make FOO=blah", then we set the
             # option 'FOO' in Options.options, to blah. If you look in wafsamba/wscript