From Tcode FBCJ calling Z print program

Hi Experts,

I have a requirement on Cash Journal receipt. In tcode FBCJ after corresponding data, and then clicking on Receipt button a stardard receipt form is being opened. But I have created a z-print program in smartform for cash journal. My requiremnt is to call my z print program on clicking the Receipt button in FBCJ, How to do this? Can anyone help me please.

Regards,

SURYA