Error opening URL

ok now i have a variable “URL”

http://+URL+/+folder+/+image (or something like that - it works anyway)

and a search box replaces the url and places it in the url as appropriate

Error opening URL “http://www.mywebsite.co.uk/blah/stupidimage.jpg

now if someone types “hello” and submit, it looks for

http://www.mywebsite.co.uk/blah/hello.jpg

but if the image isnt in the folder it will come up as

Error opening URL "http://www.mywebsite.co.uk/blah/hello.jpg in the OUTPUT box

now is their any way at all to say in the actionscript (the image searched wasnt in our database please try again) i know its a default message flash comes up with but is their a quick way to use this default error to make an “error movieclip” visible?

cheers