Decompression error(receiving)- Program will be terminated

Dear Friends,

We are running SAP 4.7 R/3 with 7.3 GUI. In which we have a program named, ZRBC. Which runs successfully & displays output for 10000 people. However, if we are running for 40000 people. After approx one hour, the following is the outcome :-

(a) On few computers, all sessions gets terminated without any error notification.

(b) On few computers, there is an error message displaying as "Decompression error(receiving)- Program will be terminated" and particular session gets terminated after clicking "OK".

Please suggest necessary actions.

Regards,

M Sridhar Srinivas