Form submission problems

Hey there,

I am attempting to update some custom user profile fields from a form submission (not from the user profile page itself). The basic premise is that I’m making an rpg-ish game and need to be able to update the user’s experience/level/etc. which I am keeping track of as a user profile field. Anyway, here is probably more code than I need, but in case you guys need to reference it, here is the stuff in my functions.php for the user profile field “experience”:

add_action( 'show_user_profile', 'my_show_extra_profile_fields' );
add_action( 'edit_user_profile', 'my_show_extra_profile_fields' );

function my_show_extra_profile_fields( $user ) { ?>

	<h3>Extra profile information</h3>

	<table class="form-table">
		<tr>
			<th><label for="experience">Total Experience</label></th>
			<td>
				<input type="text" name="experience" id="experience" value="<?php echo esc_attr( get_the_author_meta( 'experience', $user->ID ) ); ?>" class="regular-text" /><br />
				<span class="description">Your Total Experience</span>
			</td>
		</tr>
	</table>
<?php }

add_action( 'personal_options_update', 'my_save_extra_profile_fields' );
add_action( 'edit_user_profile_update', 'my_save_extra_profile_fields' );
function my_save_extra_profile_fields( $user_id ) {
	if ( !current_user_can( 'edit_user', $user_id ) )
		return false;
	update_user_meta( $user_id, 'experience', $_POST['experience'] );
}

Here is the code on the page from which I want to update the user profile:

<form id="your-profile" action="<?php bloginfo('template_directory'); ?>/updatemeta.php" method="post">
<p>
<input type="text" name="checkuser_id" id="checkuser_id" value="<?php global $current_user; get_currentuserinfo(); echo $current_user->ID; ?>" />
</p>
<div style="clear: both;">
<h4>Total Experience</h4>
<?php if ( get_the_author_meta( 'userxp' ) ) { ?>
<input name="oldxp" id="oldxp" value="<?php the_author_meta( 'experience' ); ?>" type="hidden">
<input name="userxp" id="userxp" value="<?php the_author_meta( 'experience' ); ?>" type="text" readonly>
<?php } // End check for experience ?>
</div> (Note: You can only submit scores once per day, once you submit the menu will be disabled until tomorrow)
<input name="updatexp" id="updatexp" class="btnb" type="submit" value="Update Experience">
</form>

and here is the updatemeta.php file to which I am attempting to submit the form:

<?php
include 'bloginfo('home')/wp-blog-header.php';
update_user_meta( $_POST['checkuser_id'], 'experience', $_POST['userxp'] );
?>

whenever I attempt to submit the form I get the error: “Fatal error: Call to undefined function update_user_meta() in blahblahblah/updatemeta.php on line 3” I am assuming that my updatemeta.php file is either missing some include that I can’t figure out or it’s in the wrong place (right now it’s in the template file with all my page templates). Anyway, if you knowledgeable people have any insights, I would be incredibly thankful.

Thomas