wierd text inserted randomly

[Anon]

Since I'm a PHP newbie, I'm sure there's some dumb obvious reason why this is happening, but for the life of me, I can't find it:

I've created some online ordering forms which accept customer data, store it in a text file, and email both the customer and me a response notification. It works pretty well.

But . . . one variable keeps displaying an extra "! " which show up in random locations, when the variable is echoed, like this:

$payment_method = "ProPay";
echo "$payment_method <br>"; displays "ProPay"

    so far, so good, but

$message = assorted stuff;
$message .= $payment_method; // $message being the variable containing the
email message body

    which displays:

"assorted stuff" . . . and then
"Pro! pay"

Why is this happening, but only in the concatenated variable? Why doesn't it happen in other variable, also present in the concatenated variable?

Thanks for any help.

ben
[e-mail]

PS: the email address works; spammers just assume that it doesn't.

[Anon]

Make sure you initialize $message to null before you use it.

$message="";

IMHO: Even though PHP doesn't require that you define a variable before you use it, it is a good idea to do so anyway. This is good practice in any language.