display php vars out of html

hello,

i have a problem long time and can't find help.
fckeditor modifies the html-text if there are php variables out of html-tags.

example:

<table>
<tr>
<td>test</td>
</tr>
$var1
<tr>
<td>text 2</td>
</tr>
</table>

and this is the text after:

<table>
<tbody>
<tr>
<td>test</td>
</tr>
<tr>
<td>text 2</td>
</tr>
</tbody>
</table>

is it possible to let the php variables into the text?

thanks for your help