xsl:message inside of xsl:variable

Hello,

take a look at the following template:

<xsl:template match="/">
   <xsl:variable name="message">
      <xsl:message>a message</xsl:message>
      <xsl:text>some text</xsl:text>
   </xsl:variable>

   <xsl:value-of select="$message" />
</xsl:template>

What is the expected output?
I tested this with Saxon, XT and LotusXSL/Xalan, and only Saxon seems
to do the job the way I wanted it:

a message
<?xml version="1.0" encoding="utf-8" ?>some text

I.e. "a message" is sent directly to the output (stderr), message contains
"some text".

XT and LotusXSL omit "a message".

I need this for the following kind of application.
The first step of my transformation is a check if the source document
is valid according to my constraints (of course I could separate the 
task using Schematron ...).
Every time an error is detected the stylesheet produces a message via
<xsl:message>. I want all errors to be found, and I want to stop if
one or more errors occured.

The solution I had was

<xsl:variable name="errors">
   <xsl:apply-templates mode="validate">
</xsl:variable>
<xsl:if test="string-length($errors)!=0">
   <xsl:message terminate="yes">
       <xsl:value-of select="string-length($errors)"/>
       <xsl:text> errors detected</xsl:text>
   </xsl:message>
</xsl:if>

If a template in validate mode detects an error it calls
<xsl:message>
   <xsl:text> ... error report ... </xsl:text>
</xsl:message>
<xsl:text>.</xsl:text>

That works great with Saxon! :-)
Unfortunately XT and LotusXSL omit all error reports. They just say (e.g.)
"5 errors detected", terminate, and that's all.

Is that a bug in XT and LotusXSL, or is the XSLT spec too unspecific?

Cheers,
Oliver


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|  ob|do        Dipl.Inf. Oliver Becker                             |
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