Joke.Win.Aloap is not a trojan (altough some programs report it as such) but a joke program.
After being run it starts to shake current and all further opened application windows. This works under all versions of MS Windows.
To deactivate the joke you should open Task Manager and kill 'Aloap Window' process.
Depending on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the suspect file, or ask you for a desired action.
More information on the scanning and removal options available in your F-Secure product can be found in the Help Center.
You may also refer to the Knowledge Base on the F-Secure Community site for more information.