Show Avatar on forum homepage?

[helenblog]

In FORUMHOME template, I want to show

the avatar of a member ( the person that logged into the forum )

for example:
under {vb:raw navbar}

I want to have this code

Hello, <img src="{$avatar_of_member}" alt="avatar of member">

{$avatar_of_member} is the image link of a member's avatar.

I searched on vBullletin but seem it didn't have any solutions for this.