Customer has experienced problems with Informix, including "corruption" of the database due to application of patch 119130 which is bundled within the S10 recommended patch cluster.
The problem stems from the fact that character devices under the /devices directory that they have modified (permissions, group, and owner) are altered by the patch install. They require the underlying devices to be owned by the "informix" user and group with 660 perms. After FC driver patch install, these get reset back to being owned by root and sys with 640 perms. As a result, Informix starts up and is unable to properly communicate to the devices it previously owned.
This was not an issue (at least not as much of one) in s8/s9 because the FC driver patches were unbundled and not part of the recommended patch cluster. Now that the s10 patch cluster includes 119130, the problem is compounded and they have to take extra measures during routine patching to work around this particular problem.
Work Around
To avoid the immediate impact, one would have to alter the installation routine for the cluster install to not install 119130.
Otherwise, one would have to plan for an extended outage (beyond the simple patch installations) to correct the permissions that we altered by the patch install.