sql concurrent program

Hi,

Concurrent program type sql.

It has one parameter  text.

In the sql script.

var := '&1';

some time the paramter can have  ' ( quote).

Need to replace single quote with double.

How can I do it as program fails on the assignment itself

var := '&1';  

ORA-01756: quoted string not properly terminated

replace commands also same error.

This is called by many programs. We would like to change in this one program instead of all calling program do the replace.

thanks