To permanently disable caching of php script do the following:
open file php.ini located in folder *\UniServer\usr\local\php and add:
eaccelerator.filter = "!*.php"
[eaccelerator]
extension=eaccelerator.dll
eaccelerator.allowed_admin_path=C:/UniServer/home/admin/www/plugins/eaccelerator/control.php
eaccelerator.cache_dir=C:/UniServer/tmp/eaccelerator
eaccelerator.debug = 0
eaccelerator.filter = "!*.php"
This seems to work.