Missing "R" in link created in RSVP send email

Hi
I have a different problem (I think) with the links created in the email sent from RSVP. Plus I have a problem when selecting WHO to send the email to. This issue is just for the links.

I have an RSVP, I have invited many people. I click on Send Message and type the message. The email sent includes a link that LOOKS like this:
/rsvp/email/5693049cd660fb4a9f29cb2ba2a0ed3e

BUT, the link created is:
http://www.mysite.com/svp/email/5693049cd660fb4a9f29cb2ba2a0ed3e

You can see that it says "svp" NOT "rsvp" - the R is missing making the link not work. I have looked in the code and can't see why it doesn't work (but I'm not very experienced) - this is the code that send the email link (I think)

  $body = t("Hello!\n\nYou have been sent a message by !sender at !site.\n\nYou can view the invitation from where it originated by following this link: \n!url\n\nHere is the message:\n", array('!sender' => $sender, '!site' => $site, '!url' => l("/rsvp/email/$invite->hash", "/rsvp/email/$invite->hash"))) . $edit['body'];

Could someone help me?
Thanks
Debs