to retrieve the processing instruction

hi,
can anybody let me know,how do i retrieve the value of the xslt style
sheet type and href ,which is along with the xml file using dom.
there is a createProsessingInstruction() returning a
processionInstuction referance,but there is no
getProcessingInstruction() in the Document interface
eg:
<?xml version=\"1.0\"?>");
   <?xml-stylesheet type=\"text/xsl\" href=\"xslt1.xsl\"?>")
  <a>
   <hello>hgff</hello>
   <password>jhbjh</password>
   </a>

here i need to get the type and href for the xslt.

Thanks in advance

Sridhar