Now I found that problem is in upcase letter in function definition. Following example work fine:

<?php
class myParent {
  function parentfunc() {
   echo "Parent Function Output\n";
  }
}

class myChild {
}

runkit_class_adopt('myChild','myParent');
myChild::parentfunc();
myChild::parentFunc();

?> 



And one another example which may help with bug fixing:

<?php
class myParent {
  function parentFunc() {
   echo "Parent Function Output\n";
  }
}

class myChild {
}

runkit_class_adopt('myChild','myParent');

var_dump(get_class_methods ('myChild'));
var_dump(get_class_methods ('myParent'));

myParent::parentFunc();
myChild::parentFunc();

?> 





The result is this:

array(1) {
  [0]=>
  string(10) "parentFunc"
}
array(1) {
  [0]=>
  string(10) "parentFunc"
}
Parent Function Output


Fatal error:  Call to undefined method myChild::parentfunc() in D:\data\http\pokus\runkit.php on line 17

This bug has been fixed in CVS.

In case this was a documentation problem, the fix will show up at the
end of next Sunday (CET) on pecl.php.net.

In case this was a pecl.php.net website problem, the change will show
up on the website in short time.
 
Thank you for the report, and for helping us make PECL better.

Thanks for the detailed bug report!