Help please with Informix C-Isam datatype

I would really appreciate some help on the following... I have C-Isam application files on an RS/6000 server. According to the application documentation, certain field datatypes stored on these C-Isam files are "zoned signed". Can anybody please give me a bits and bytes layout for fields defined as "zoned signed"? We have a Sybase OmniCONNECT server that maps onto these C-Isam files. It does not have an automatic translation for these datatypes. I can define them as binary columns which shows me the numbers but the last byte of the column appears as a funny character. I have determined from the limited samples that I displayed hex values of either x'7b' or x'42'. Somewhere in this last byte is I would imagine as the sign and the decimal place. The column contains such information as currency. If anyone can help or point me in the right direction, I would really appreciate it. Thanks again, Joe Leong.