I discovered today (the hard way), that we can no longer use xsl:include and xsl:import elements in XSL Transformations for Windows SharePoint Services 3.0 XML WebParts.

Along with those msxml:script is also blocked.

I am going to investigate this further and see if there is an administrative way to bypass this security restriction. XSLT code reuse is a useful thing and I want to keep it as an option in some environments.

Anyhow...

I am including two relevant links I found on the web:
I would appreciate comments from people who know more on the subject.