ice:commandButton currently does not support any <f:param> so if you do the following in compat showcase:-
      <ice:outputLabel for="BLCmdBtn"
                         value="#{msgs['page.buttonsAndLinks.submitButtonLabel']}"/>
        <ice:commandButton id="BLCmdBtn"
                           value="Submit"
                           actionListener="#{buttonsAndLinks.submitButtonListener}">
                     <f:param name="fileId" value="21"/>
        </ice:commandButton>

you get the following markup:-
<input class="iceCmdBtn" id="iceform:BLCmdBtn" name="iceform:BLCmdBtn" onblur="setFocus('');" onclick="iceSubmit(form,this,event);return false;" onfocus="setFocus(this.id);" type="submit" value="Submit">

if you do the same thing with <h:commandButton> you get the following:-

<input id="fileform:fileTable:0:delFileBtn" name="fileform:fileTable:0:delFileBtn" onclick="mojarra.jsfcljs(document.getElementById('fileform'),{'fileform:fileTable:0:delFileBtn':'fileform:fileTable:0:delFileBtn','fileId':'1'},'');return false" type="submit" value="Delete">

Note with <ice:commandButton> there is no encoding of the parameter name or value so it never gets submitted to the server.