ns-cron problems with nsapi-Webdriver Module on Enterpris Server 3.5.1

we are using the webdriver nsapi-Module of Webdatablade 3.32.UC4 on a Netscape Enterprise Server 3.5.1 to connect to an IDS 9.14.UCx. Both running on Solaris 2.6 on a SUN enterprise. If we are using ns-cron for log rotating the NS-Server stopps sometimes (process still there but its not answer any request), but only if the log rotating is done by ns-cron. Netscape told us that the Infomix Module should be the reason for that, but I'm not sure. Does anybody knows something about this problem? Thanks and Bye Dirk