This little gem causes a regression. Because cache->handle is left NULL, we never cleanup stale entries in the cache (in cache_save_filter). Once CacheMaxExpires hits, the stale entry will never be garbage collected from the cache and replaced by a new entry. Two ways to fix this come to mind right off hand (neither are optimal i expect):
Well, I don't know about mod_mem_cache, but I don't believe this affects mod_disk_cache. mod_disk_cache overwrites the old entry if it is told to do so. It's possible that mod_mem_cache should do the same.
FWIW, your 2 patches are identical. Not sure if that's what you intended or not. ;-) -- justin