[Chameleon] Interference with PHP's Garbage Collection

[Abe Gillespie]

I'm trying to pin down a problem with PHP's session tmp directory
growing out of control.  The problem grabbed my attention when a
customer's server ran out of space.  At that point the session
directory was 13.5G!

I set the probability of garbage collection to 100 / 100 ... or
"always collect."  This has not helped since I see files beyond the
default age of 1440 seconds.

Anyone else experiencing this or have a clue what I'm missing?

System:
The only PHP app is Chameleon.
Chameleon 2.2
Apache 2.0.54
PHP 4.4.0

All php.ini settings are default as included with php.ini.recommended
except for:
session.gc_probability = 100
session.gc_divisor     = 100

Help is greatly appreciated.
-Abe