sqlldr : charset conversion while loading ?

Hi,
I am a newbie to Linux(Suse).I am facing a problem with 'sqlldr' utility while trying to upload data to Database tables.My backend is Oracle and is using the UTF8 encoding format.I am trying to load a datafile which contains some Western European Characters.While loading am getting an error 'value too large for column'.I think the charset conversion was not successful.

Can anyone please suggest how to move forward?

FYI. This issue happenend after the upgradation of my server from SUSE8 to SUSE9.Is there any settings or configuration file related to this as a part of Oracle client ?

Your help is appreciated.

With Regards
Dileep Pattayath