Event for BUS2032

[Schmidinger, Heinz (Unaxis IT BZ)]

Dear Collegeous,
 
I'm looking for a point to fire an Customer -Event for BUS2032 (Sales Order)
in  SAP 6.20.
Unfortunally the needed Fields (VBUK-GBSTK) is not in the Change-Document.
Also I found no Customer-Exit  or BADI for on-save.
 
Has anyone of you expirence where I can place my f.m. to fire the Event if
VBUK-GBSTK changes..
 
 
Many thanks in advance.
 
regards
 
Heinz