Question about Postparsed

[jfxcube]

i need to change pagetext field in post table but when i do it with an external query or using tools like phpmyadmin the modify is sucessful and the content of the field is correctly updated in the db, the problem is that is not showing up in the corresponding thread in the forum (it keep the old content, guess cause of something inserted in the post parsed table).

I need to make this editing directly on the table in the db to avoid to make change in the forum script.
There is some way to avoid this problem????