The original (EN) code is: <PossessiveProperNoun T="(s$)=$1':(.$)=$1's:" /> which returns Alices and Charles'.  But I wanted to get rid of the terminating apostroph.

I've tried following combinations but they don't deliver the expected result.

T="([sxz]$)=$1:([^sxz])=$1s:"               returns Aslice and Csharles
T="([sxz]$)=$1:(.$)=$1s:"                      returns Alices (OK)  and Charless
T="(s$)=$1:(x$)=$1:(z$)=$1:(.$)=$1s:" returns Alices (OK)  and Charless

Can anybody tell me what I'm doing wrong?

PS: I was unable to use script56.chm as documented but found information at http://msdn.microsoft.com/en-us/library/6wzad2b2.aspx

<PossessiveProperNoun T="([^ sxz]$)=$1s:" />

This code means: if not (the '^') ending (the '$') with s, x or z, append an 's' at the end.

I tried it with my tree and it looks OK.

JC

Update: the script56.chm file can be downloaded at MS:

http://www.microsoft.com/downloads/details.aspx?FamilyId=01592C48-207D-4BE1-8A76-1C4099D7BBB9&displaylang=en

Turns out that I forgot the "$" after "[^sxz]".  That's the sort of error you don't see when you wrote it yourself.