Showing someone's Username On a Html or php page

[MissKalunji]

okay lemme try to explain

the invite system only sends plain e-mail
i want it to send it in html format

how can i do it?

so far what ive done is included the invitemessage.html

but inside the invitemessage.html it shows as

$bbuserinfo has invited you to dhaz.com....

$bbuserinfo <-- should be showing the person's nick name
and i want to know what should i insert in the heading
for it to show when its send the person's username

or

how to make the mod send html e-mail instead of plain mail