Potential memory leak

[mxxcon]

Ubuntu server 10.04LTS, Apache 2.2.14-5ubuntu8.2, XCache 1.3.0-5ubuntu1.

xcache.shm_scheme =        "mmap"
xcache.size  =                64M
xcache.count =                 2
xcache.slots =                8K
xcache.ttl   =                 0
xcache.gc_interval =           0
xcache.var_size  =            0M
xcache.var_count =             1
xcache.var_slots =            8K
xcache.var_ttl   =             0
xcache.var_maxttl   =          0
xcache.var_gc_interval =     300
xcache.test =                Off
xcache.readonly_protection = Off
xcache.mmap_path =    "/dev/zero"
xcache.coverager =          Off

After a while the server starts to use up all available memory and then all available swap and then becomes unresponsive. Tried adjusting xcache.ini settings without change in behavior. Switching XCache for APC makes the server stable again.
attached in a screenshot of cacti's monitoring memory usage. toward the end of the graph is when we switched to apc.

[mxxcon]

cacti graph of memory usage

[moo]

dup of #258