Re: excel.la has no valid dlname?

[Morten Welinder <terra diku dk>]

   checking whether the linker (/usr/bin/ld) supports shared libraries... yes
   checking how to hardcode library paths into programs... immediate
   checking whether stripping libraries is possible... yes
   checking dynamic linker characteristics... no
   checking if libtool supports shared libraries... no
   checking whether to build shared libraries... no
   checking whether to build static libraries... yes

Well, there is your problem.  Your libtool installation is bad.
Gnumeric's plugins require dynamic linking, i.e., dynamic libraries.

Morten