Messages with URL after the sign-off word disappear into the ether!

[TM]

Hi - I wonder if anyone has any suggestions to help with this wierd
problem.

I use Outlook 2003. I'm finding that, if I just end my message

John Doe

the message goes out and is received OK.

If however, I end the message (for example)

John Doe
http://groups.google.co.uk/group/microsoft.public.outlook.usage/post?hl=en

the message appears to leave my Outbox, but that's it! It shows up in
my Sent box, but it's never received at the other end.

I can't say whether this happens on every occasion - I don't always
know what people don't receive - but it is happening.

Any thoughts as to why will be greatly appreciated