Reproduction Procedure:

1) Define a IBase interface and put some methods int it (Base1, Base2, Base3).
2) Then define two more interfaces derived from IBas (IDerived1, IDerived2).
3) All the methods are called differently, so, is not a problem of ambiguous overloading.
4) Then make a class to implement the two derived interfaces (TTestCase).
5) Then in that class provide two sets for the IBase's methods, and implement each of the interfaces redirecting it's methods to the respective set.

For a real world example, see the code in:
http://cvs.sf.net/viewcvs.py/sil/152/

this [1, http://tinyurl.com/r2mzv]:
source/lib/SilLiDataType.pas

In that context is:
IBase == IDataTypecast, and
IDerived1 == IDataConvert,
IDerived2 = IDataAssing.

All this are implemented in[2, http://tinyurl.com/r9w9n]: source/lib/SilLiDataType.pas

And see[3, http://tinyurl.com/zrvow]:

programs/
demos/
lib/
framework/
conversion/
FmTestBaseFrameworkConversion.pas

for an example of how it is used.

Thanks, hope this helps.
Leandro.

[1]
http://cvs.sf.net/viewcvs.py/sil/152/source/lib/SilLiDataType.pas?rev=1.7&vi ew=markup

[2]
http://cvs.sf.net/viewcvs.py/sil/152/source/lib/SilLkDataHandler.pas?rev=1.9 &view=markup

[3]
http://cvs.sf.net/viewcvs.py/sil/152/programs/demos/lib/framework/conversion /FmTestBaseFrameworkConversion.pas?view=markup

Fixed, Thanks for the test

Guau!! That's speed! :)

Thanks to you, indeed!

By the way, I've managed to compile my library with FPC 2.0.2!! It needed some major changes and some extra work to bypass some units that still are relying on things not yet implemented in FPC (like the "implements" keyword).

I've run a few tests and the basics are working right now ... I'm really glad!!

Thank you again.
Leandro.

PS:
By the way, I've detected some problems with many overloaded functions that Delphi compiles ok, but FPC complains with ambiguous parameters while calling.
This week I'll be working on a new test case for sending to you about this problems.