javascript code on display in browser window

Hi all,

The problem I'm having occurs sporadically. Sometimes javascript code will be spit out into the browser window instead of what is supposed to be displayed. Has anyone else encountered this problem frequently? What causes it? My program uses two windows and it is the child window that does this initially. When I revisit the location again, the parent window then has the same problem. Is it a synchronization problem? How could I fix it?

Thanks for any help,
Jane