Cannot open Interactive sql from command prompt

I have added my own procedure to run as soon as user logs, using

SET OPTION PUBLIC.post_login_procedure = 'xxx.Myprocedure';

I need to set custom message on pop up this provides when user logs in. The pop up is working, when I manually login in from Sybase central. however, when I run dbisql -c "DSN=myDSN" from command prompt Interactive sql opens and I get the popup that stays on forever!

I get this pop up only when I have set the popup to appear through post_login_procedure , If i remove that then I can connect to interactive sql without any problem.

Please help, Thanks