Informix 4.x problems with SCO Unix

Hello all, we are experiencing a severe problem with Informix 4GL Versions 4.1x running on SCO Unix 3.2.2, 3.2.4.0 and 3.2.4.2. We have installed the International Supplement available from SCO. Whenever a 4GL program reads text in an INPUT or INPUT array statement, and that text contains German umlauts (special characters), these characters are displayed as "?" (a question mark) whenever the data is redislayed or the user enters the input field again. The data is, however, contained correctly in the database. This doesn't occur with all Umlauts, with DEC Multinational character mapping this happens to "A, "o and "u. By experminenting with the SCO mapchan facility, I found a set of mappings that will work with our system, but shows different behaviour with several other system (same SCO release, identical programs). *** THIS PROBLEM IS DRIVING ME NUTS !!! *** Informix technical support Germany wasn't able to help; the only statement we got from them was : "It works with our SCO ODT system". :-( We don't have the problem with the identical sources compiled on a TI BS1500 or IBM RS/6000. But, the very same problem occurs when running these programs under iBCS (SCO emulation) on a Linux system. So, it can't be too OS specific, I suppose... If anybody has a hint what I can do, _please_ mail me ! Thanks a lot, Michael Engel (engel@numerik.fb6.uni-siegen.de)