diff --git a/gzdoom.spec b/gzdoom.spec
index a103547..9d68d97 100644
--- a/gzdoom.spec
+++ b/gzdoom.spec
@@ -75,6 +75,8 @@ GZDoom is a port (a modification) of the original Doom source code, featuring:
 %setup -qn gzdoom-g%version
 %patch -P 1 -P 2 -p1
 perl -i -pe 's{__DATE__}{""}g' src/posix/sdl/i_main.cpp
+perl -i -pe 's{<unknown version>}{%version}g' \
+	tools/updaterevision/updaterevision.c
 
 %build
 # We must not strip - %%debug_package will take care of it