convert-ly and partcombine

[Tapio Tuovila]

Hi,

I tried to convert Aase's death from Mutopia-2002/07/04-247, originally 
typeset with lilypond 1.5.63.
My version is 2.4.2.
convert-ly gives the following:
>>/Lilywork> convert-ly violiniIpart.ly
>>/usr/local/bin/convert-ly (GNU LilyPond) 2.4.2
>>Processing `violiniIpart.ly' ... Applying conversions: 1.5.67, 
1.5.68, 1.5.71, 1.5.72, 1.6.5, 1.7.1, 1.7.2, 1.7.3, 1.7.4, 1.7.5, 
>>1.7.6, 1.7.10, 1.7.11, 1.7.13, 1.7.15, 1.7.16, 1.7.17, 1.7.18, 
1.7.19, 1.7.22, 1.7.23, 1.7.24, 1.7.28, 1.9.0, 1.9.1, 1.9.2, 1.9.3, 
>>1.9.4, 1.9.5, 1.9.6, 1.9.7, 1.9.8, 2.1.1, 2.1.2, 2.1.3, 2.1.4, 2.1.7, 
2.1.10, 2.1.11, 2.1.12, 2.1.13, 2.1.14, 2.1.15, 2.1.16, 2.1.17, 
>>Warning: \partcombine has been changed. Check conversion 
manually!Error while converting; I won't convert any further

Now, what could be done with this? Where can I find documentation of the 
changes of \partcombine and how to 'check conversion manually'? Is there 
any workaround?

greetings,
Tapio