conv.m compatibility

[John W. Eaton]

On 14-Apr-2008, Moritz Borgmann wrote:

| After the discussion, I tend to retract my original patch in favor of 
| another one that doesn't change functionality, but makes the output 
| orientation explicit in the documentation - and fix the code that 
| makes assumptions about the orientation of the output.

Was there a patch submitted for this change?  If so, I think I missed it.

jwe