Error by extraction element with xml-encoded characters using openxml @mp:xmltext metaproperty

[#1]

I have a problem when using OPENXML function over data containing xml-encoding unicode character. The following example returns error: Control character in XML output!

select * from openxml( '<root><element>&#xE6;</element></root>', '/root') with (element xml 'element/@mp:xmltext');

But this one without metaproperty: @MP:xmltext is correct:

select * from openxml( '<root><element>&#xE6;</element></root>', '/root') with (element xml 'element');

The last character, which does not cause a problem is &#xB8.

Used server dbsrv11.exe 11.0.1.2837 runnig on W2003 and the database was generated by command:
dbinit.exe -a -p 4096 -ze cp1250 -z uca(locale=sk)

Thank you for help