Ok people:

I have just discovered that you need to do the first sync using the old fashion way - through cable. If you don´t do that, hotsync will not create the sync.ini file inside the profile folder (C:\Program Files\palmOne\user) and you won´t be able to select it on the hotsync manager to do your sync (even hotsync manager warns you that if you don´t do the first sync, you will get problems).
To do the sync itself, I´m going to visit my client tomorrow and test it. I hope it works, because I really want to deliver it working fine.

Once again, tks for all the help! Will let you know the results.