PHP - Dos combobox en diferentes formularios

<table style="float: right;" cellspacing="0" cellpadding="0" class="listados">

	<tr>

		<th class="filtro">

			<form id="categoria" action="../vueltas/<?php echo $_SESSION["IDVuelta"]; ?>" method="post">

			<div align="right"><b>categoria:</b>&nbsp;

			<SELECT NAME="categoria" SIZE=1 onChange="submit()">

			<OPTION <?php if(!isset($_POST['categoria']) || strcmp($_POST['categoria'], 'todas')==0){echo "selected "; } ?> VALUE="todas">TODAS</OPTION>

			<?php while ($resCT = mysql_fetch_array($queCT)) { ?>

			<OPTION <?php $CateFI = $resCT['IDCateT08']; if(strcmp($_POST['categoria'], $CateFI)==0){ echo "selected "; } ?>VALUE="<?php echo $resCT['IDCateT08']; ?>"><?php echo $resCT['NombreT08']; ?></OPTION>

			<?php } ?>

			</SELECT>

			</div>

			</form>

		</th>

		<th class="filtro">

			<form id="sexo" action="../vueltas/<?php echo $_SESSION["IDVuelta"]; ?>" method="post">

			<div align="right"><b>sexo:</b>&nbsp;

			<SELECT NAME="sexo" SIZE=1 onChange="submit()">

			<OPTION <?php if(!isset($_POST['sexo']) || strcmp($_POST['sexo'], 'todas')==0){echo "selected "; } ?> VALUE="todas">TODAS</OPTION>

			<?php while ($resCO = mysql_fetch_array($queCO)) { ?>

			<OPTION <?php $SexoFI = $resCO['IDSexoT06']; if(strcmp($_POST['sexo'], $SexoFI)==0){ echo "selected "; } ?>VALUE="<?php echo $resCO['IDSexoT06']; ?>"><?php echo $resCO['NombreT06']; ?></OPTION>

			<?php } ?>

			</SELECT>

			</div>

			</form>

		</th>

	</tr>

</table>

//SI NO HAY NINGUN FILTRO SELECCIONADO

if(!isset($_POST['categoria'])|| strcmp($_POST['categoria'], 'todas')==0 AND !isset($_POST['sexo'])|| strcmp($_POST['sexo'], 'todas')==0){

.................................... }

else {

//SI SE HA SELECCIONADO FILTRO SEXO

if (!isset($_POST['categoria']) || strcmp($_POST['categoria'], 'todas')==0 ) {

.................................... }

//SI SE HA SELECCIONADO FILTRO CATEGORIA

elseif (!isset($_POST['copa']) || strcmp($_POST['copa'], 'todas')==0 ) {

.................................... }

//SI SE HAN SELECCIONADO LOS DOS FILTROS

elseif(isset($_POST['categoria'])|| strcmp($_POST['categoria'], 'todas')==0 AND isset($_POST['sexo'])|| strcmp($_POST['sexo'], 'todas')==0){

.................................... }