There's probably a few ways to do this..and this may not be the best solution. However, in the package I'm developing right now I'm saving attributes using this method:

$uo->setAttribute($handle, $value);

$uo is a UserInfo object.

The reason I say this is probably not the proper way is due to the different data formatting required by some attributes (namely the 'address' attribute which, for example, requires a specific array of data passed to setAttribute.)

I'm just getting into C5 programming so I'm a bit weak, but hope this helps point you in a direction.

I have the same question!

@bolder what did you end up doing? Did drm"s solution do the trick?

Does anyone have any updates to this?

I don't remember exactly how I solved this since it was a while ago, I'll see if I can dig up the code in the next couple days and I'll post it up here for ya.