Database connections not being released in a timely manner

[ilikebundy]

We have found that since upgrading to 11.1.7FP1 also tried FP3 we are getting database connections staying active for 60 min despite the CQEConfig.xml timeout being set to 900sec.  test was done as follows:
change CQEConfig.xml - timeout to 10sec - max connections to - 10.
restart cognos
run report "CQM non interactive" - 7 connections established to informix source database.
Close Report.
db connections stay until 60min has elapsed then are discarded.

Retry with 11.0.13
repeat above test.
db connections discarded after timeout setting of 10sec.

Seems to be a bug in 11.1.7.

Has anyone else seen this since upgrading from 11.0.13?

Could this be a config that has changed in 11.1.7?

Any help appreciated
Have logged a ticket with IBM but nothing yet

Mike