Comment 2 for bug 603661

As a workaround, deleting the contents of ~/.moc/cache worked for me.

Notice these errors when running the server process on the foreground with "mocp -S -F":

...
Build signature doesn't match environment
Jul 24 13:36:15.049617: tags_cache.c:957 tags_cache_load(): Can't open DB environment (/home/svm/.moc/cache): DB_VERSION_MISMATCH: Database environment version mismatch
...

It then crashes in tags_cache.c:tags_cache_add_request() on line 680:

db_ret = c->db_env->lock_get (...)

but c->db_env points to null.

(I can't debug this any deeper right now, but I thought I'd post this anyway so people know there's a workaround.)