[Aken]

This is the code for the buttons. Simple add your image where appropriate.

			<!-- controls -->
			<if condition="$post['editlink']">
				<a href="$post[editlink]" name="vB::QuickEdit::$post[postid]"><img src="$stylevar[imgdir_button]/edit.gif" alt="$vbphrase[edit_delete_message]" border="0" /></a>
			</if>
			<if condition="$post['forwardlink']">
				<a href="$post[forwardlink]"><img src="$stylevar[imgdir_button]/forward.gif" alt="$vbphrase[forward_message]" border="0" /></a>
			</if>
			<if condition="$post['replylink']">
				<a href="$post[replylink]" rel="nofollow"><img src="$stylevar[imgdir_button]/<if condition="$post['forwardlink']">reply_small<else />quote</if>.gif" alt="$vbphrase[reply_with_quote]" border="0" /></a>
			</if>
			<if condition="$show['quickreply'] AND !$show['threadedmode']">
				<a href="$post[replylink]" rel="nofollow" id="qr_$post[postid]" onclick="return false"><img src="$stylevar[imgdir_button]/quickreply.gif" alt="$vbphrase[quick_reply_to_this_message]" border="0" /></a>
			</if>
			<if condition="$show['moderated']">
				<img src="$stylevar[imgdir_misc]/moderated.gif" alt="$vbphrase[moderated_post]" border="0" />
			</if>
			<!-- / controls -->

The code is the same in both the postbit and postbit_legacy templates. Make sure to change the one(s) you use!