The calculation of an internal value used in determining the maximum number of remote caches was calculated incorrectly, producing a number in the vicinity of 250. If the number of remote caches attached to a system grew larger than this, an assertion check using this incorrect limit was hit, and the Stone crashed with a UTL_GUARANTEE error.
If you expect to have sessions distributed over a large number of remote machines, you should upgrade to a version in which this bug is fixed.
Last updated: 3/11/15