set(REGRESSIONTEST_VERSION "${GMX_VERSION_STRING}")
set(REGRESSIONTEST_BRANCH "refs/heads/master")
-set(REGRESSIONTEST_MD5SUM "366438549270d005fa6def6e56ca0256")
+set(REGRESSIONTEST_MD5SUM "366438549270d005fa6def6e56ca0256" CACHE INTERNAL "MD5 sum of the regressiontests tarball")
math(EXPR GMX_VERSION_NUMERIC
"${GMX_VERSION_MAJOR}*10000 + ${GMX_VERSION_PATCH}")