p:output binding errors in Calabash

It is a static error (err:XS0029) to specify a binding for a p:output inside
a p:declare-step for an atomic step.

Calabash 0.6.0 does not seem to be catching this error.  I tested a handful
of steps, and it¹s not reporting any errors.  The following all work fine:

p:delete:

<p:declare-step xmlns:p="http://www.w3.org/ns/xproc">
    <p:input port="source" primary="true">
        <p:document href="BookStore.xml"/>
    </p:input>
    <p:output port="result"/>
    <p:delete match="/BookStore/Book/Title">
        <p:output port="result"/>
    </p:delete>
</p:declare-step>

p:directory-list:

<p:declare-step xmlns:p="http://www.w3.org/ns/xproc">
    <p:input port="source"/>
    <p:output port="result"/>
    <p:directory-list path=".">
        <p:output port="result"/>
    </p:directory-list>
</p:declare-step>

p:filter:

<p:declare-step xmlns:p="http://www.w3.org/ns/xproc">
    <p:input port="source">
        <p:document href="Bookstore.xml"/>
    </p:input>
    <p:output port="result"/>
    <p:filter select="/BookStore/Book[Date='1998']">
        <p:output port="result"/>
    </p:filter>
</p:declare-step>

I suspect that there are many more steps that are allowing this.  :-(

James Garriss
http://garriss.blogspot.com