.extern module in IL files

Question

I am unable to get any satisfactory explanation of the .extern module directive in IL manifests. What does this directive mean? Any help is appreciated.

Also, I would like to know that if I strong name an assembly, do I also need to strong name the .net modules listed in .extern modules section?

EDIT:

As Hans Passant pointed out, the directive is invalid. The correct directive is '.module extern'

Answer 1

It is a reference to a external library. I do believe it just specifies what assembly to load, and I believe optionally where to find it, what version and if it should be signed.

See also http://jilc.sourceforge.net/ecma_p2_cil.shtml