How about something like this?
<xsl:value-of select="count(//MOP[number(.)&gt;0])"/>

Cheers,
Wendell

> This is the situation: I need to get the number of currently open account
> (which is indicated by MOP element), If MOP value is a number, not a
> 2-char-code, then the current account is opened, otherwise it's close. The
> MOP number could be 01 - 09. This is the xml:

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Wendell Piez                            mailto:wapiez@xxxxxxxxxxxxxxxx
Mulberry Technologies, Inc.                http://www.mulberrytech.com
17 West Jefferson Street                    Direct Phone: 301/315-9635
Suite 207                                          Phone: 301/315-9631
Rockville, MD  20850                                 Fax: 301/315-8285
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