template which parametrizes another template call

Hi,

i want to output many different table cells which follow exactly the
same layout. Data to be output comes in a raw format. It must be
transformed to a readable format. Therefore my layout template should
call a template to transform the data, using a output transformer which
is given by parameter.

So i wrote the following template:

	<xsl:template name="outData">
		<xsl:param name="f_inhalt"/>
		<xsl:param name="f_inhaltFormatter"/>
		..... do some layout things
		<xsl:call-template name="$f_inhaltFormatter">
			<xsl:with-param name="param"
select="$f_inhalt"/>
		</xsl:call-template>
		.... do some more layout things
	</xsl:template>

If i run this i get an Error "template with name f_inhaltFormatter not
found"
It seems as if "f_inhaltFormatter" is not recognized as Variable but as
string.

Does anybody know a good solution for my problem?

Best regards,
Thomas