Content Encoding Error when adding template to a template hook

[p0lar_bear]

So I've got a popup menu that I have set to appear in postbits. It refers to a bunch of custom profile fields that make up a user's computer specifications. It works fine if I leave it in the postbit template, but I wanted to put it into a plugin instead.

My HTML is saved as a template bit named "postbit_extra_fields_popup," and it's as follows:

<!-- post specs menu -->
<div class="vbmenu_popup" id="specs_$post[postid]_menu" style="display:none">
	<table cellpadding="4" cellspacing="1" border="0">
	<tr>
		<td class="thead">$post[username]'s PC Specs</td>
	</tr>

	<if condition="$post[field6]">
		<tr><td class="vbmenu_option">Processor: $post[field6]</td></tr>
	</if>

	<if condition="$post[field7]">
		<tr><td class="vbmenu_option">Motherboard: $post[field7]</td></tr>
	</if>

	<if condition="$post[field8]">
		<tr><td class="vbmenu_option">Graphics Card: $post[field8]</td></tr>
	</if>

	<if condition="$post[field9]">
		<tr><td class="vbmenu_option">Memory (RAM): $post[field9]</td></tr>
	</if>

	<if condition="$post[field10]">
		<tr><td class="vbmenu_option">Primary Hard Drive: $post[field10]</td></tr>
	</if>

	<if condition="$post[field11]">
		<tr><td class="vbmenu_option">Secondary Hard Drive: $post[field11]</td></tr>
	</if>

	<if condition="$post[field12]">
		<tr><td class="vbmenu_option">Tertiary Hard Drive: $post[field12]</td></tr>
	</if>

	<if condition="$post[field13]">
		<tr><td class="vbmenu_option">Quaternary Hard Drive: $post[field13]</td></tr>
	</if>

	<if condition="$post[field14]">
		<tr><td class="vbmenu_option">Primary Optical Drive: $post[field14]</td></tr>
	</if>

	<if condition="$post[field15]">
		<tr><td class="vbmenu_option">Secondary Optical Drive: $post[field15]</td></tr>
	</if>

	<if condition="$post[field16]">
		<tr><td class="vbmenu_option">Power Supply: $post[field16]</td></tr>
	</if>

	<if condition="$post[field17]">
		<tr><td class="vbmenu_option">Case: $post[field17]</td></tr>
	</if>

	<if condition="$post[field18]">
		<tr><td class="vbmenu_option">Sound Card: $post[field18]</td></tr>
	</if>

	<if condition="$post[field19]">
		<tr><td class="vbmenu_option">Primary Monitor: $post[field19]</td></tr>
	</if>

	<if condition="$post[field22]">
		<tr><td class="vbmenu_option">Secondary Monitor: $post[field22]</td></tr>
	</if>

	<if condition="$post[field20]">
		<tr><td class="vbmenu_option">Operating System: $post[field20]</td></tr>
	</if>

	</table>
</div>
<!-- / post specs menu -->

My plugin is called at the "postbit_display_complete" hook, and looks like this:

PHP Code:

eval('$template_hook[postbit_end] .= "' . fetch_template('postbit_extra_fields_popup') . '"'); 


Loading any page with a postbit results in Firefox throwing an error page at me titled "Content Encoding Error." Why am I getting this error?