Security Trimming and Advanced Search

Question: Does the security-trimmer influence search bahaviour?

We are using a Business-Data-Catalog to import external data to SharePoint Server 2007.
We mapped most of the crawled properties to the SharePoint-Server managed properties and crawled the data.

Behaviour without using a Security-Trimmer:

Everything works fine. The inclusion-parameters (contains/contains not) in advanced search and search managed properties of type datetime as well.

Behaviour using a Security-Trimmer:

After security-trimmer registration the inclusion-parameters (contains/contains not) and search by using datetimes don't work anymore.
All other functionality of search is still working. The security-trimming-process also works fine. There are no exceptions.

Thanks in advance

Andreas Bolz