Ok I fixed the javascript error by inserting the file "CuteEditor_Uploader_Resource.axd" on the root of my site.
However, there is a new error that poped-out "Error,http,401" (Access denied)
Do you have any ideas on how to fix this?
--edited---
going through the previous posts, I've already tried adding "UploadType="iFrame"" to the code and it doesn't do a thing.