IIS 6.0 and .NET DLL dependency

I have a 2003 server running IIS 6.0. We have an application running
on this server (Moodle) that requires a certain PHP extension
(php_dblib.dll, a windows port of the FreeTDS database connector). I
was banging my head against the wall for some time because this
extension would load on one server but not on another one. I've
discovered that the culprit is that the php_dblib.dll has a library
dependency on MSVCR71.dll. The server that this extension refuses to
load on has had .NET 2.0 installed on it. If I install .NET 2.0 on
the server that DOES work...it stops working. Uninstall .NET 2.0 and
it starts working again. Now, before I remove .NET 2.0 from the OTHER
server (I'm 99% certain it's not needed, but it's that darn 1% that'll
get ya every time) is there a way around this dependency? I checked
the settings in IIS for the affected website and it is set to use the
1.1 version of .NET so I would assume that that means it would look in
that .NET version's directories for any libraries it needs.....is that
not the case?