This is a known issue and it has been fixed in the coming version 6.0.
Here is a work-around.
On the top of your page if you have the following code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-ransitional.dtd">
Please remove it and try again.
The following thread discusses this issue as well:
http://cutesoft.net/forums/20824/ShowPost.aspx
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