Problems with a form in first post

[Reeve of shinra]

I placed the form below in the postbit template.

Here the thing, it works perfectly on every post EXCEPT teh first where it seems to redirect me to inlinemod.php with the following error: "You did not select any posts to which the action you picked can be applied."

Does anyone know where the conflict might be?

 <if condition="is_member_of($bbuserinfo, 5, 6, 7)">
<div>
<form action="gilupdate.php" method="post" name="gilform">
<input type="hidden" name="postid" value="$post[postid]">
<input type="hidden" name="userid" value="$post[userid]">

<input type="text" name="amount" size="3">&nbsp;
<input type="image" src="images/coin.gif" border="0" name="submit" alt="Give Points" onClick="javascript:alert('Points Paid!');">

</form>
<br />
<br />
</div>
<div class="smallfont">
Post Points: $post[gilpaid]
</div>
</if>