Check if node contains value XSLT

I have the following xml:

<Reply>
  <OptionInfoReply>
    <Option>
       <Opt>EDIFBEB </Opt>
       <OptionNumber>4974</OptionNumber>
       <OptAvail>-3 </OptAvail>
    </Option>
    <Option>
       <Opt>CHSFBEB </Opt>
       <OptionNumber>2664</OptionNumber>
       <OptAvail>-3 </OptAvail>
    </Option>
    <Option>
       <Opt>WESFBEB </Opt>
       <OptionNumber>4196</OptionNumber>
       <OptAvail>-3 </OptAvail>
   </Option>

And anthoer XML which I used in for each :

<Reply>
  <OptionInfoReply>
    <Option>
      <Opt>CHSFBEB</Opt>
      <OptionNumber>3823</OptionNumber>
      <OptionNotes>
        <OptionNote>
          <NoteCategory>XM</NoteCategory>
          <NoteText>P2B</NoteText>
          <LastUpdate>2010-11-03T15:33:18Z</LastUpdate>
       </OptionNote>
     </OptionNotes>
   </Option>
  </OptionInfoReply>
</Reply>

And I want to check in XSLT if the value of for each CHSFBEB from the second XML exists in the first xml.

 <xsl:template match="/">
<db:InputParameters>
  <db:P_RESPONSE_LINES>
    <xsl:for-each select="/Reply/OptionInfoReply/Option">
      <db:P_RESPONSE_LINES_ITEM>
       <xsl:variable name="SearchOPT"  select="Opt"/>
        <db:AVAILABLE_ROOMS_NO>
         <xsl:value-of      select="$AVL/Reply/OptionInfoReply/Option/Opt[contains(.,$SearchOPT)]/../OptAvail"/>
        </db:AVAILABLE_ROOMS_NO>
                </db:P_RESPONSE_LINES_ITEM>
    </xsl:for-each>
  </db:P_RESPONSE_LINES>
  </db:InputParameters>
</xsl:template>

However, if in the first XML I have more than one option, contains is not working.