Extrange Response from IIS 6.0 / ASP .NET 2.0 Application

[reinaldo.aru]

I have a web application deployed in IIS 6.0, in Windows Server 2003.

While doing some testing, randomly I get weird reponses like this:

-----------------------------7d83a932d0356 Content-Disposition: form-data; name="ctl00_PageContentUser_ToolkitScriptManager_HiddenField" ;;AjaxControlToolkit, Version=1.0.10618.0, Culture=neutral, PublicKeyToken=28f01b0e84b6d53e:es-VE:bc82895f-eb24-48f8-a8ba-a354eb9c74da:e2e86ef9:1df13a87:c4c00916:9ea3f0e2:9e8e87e9:4c9865be:ba594826:c76f1358:69ce9abf:80f47b59:83b0cef6:d7738de7:a6a5a927 -----------------------------7d83a932d0356 Content-Disposition: form-data; name="__EVENTTARGET" -----------------------------7d83a932d0356 Content-Disposition: form-data; name="__EVENTARGUMENT" -----------------------------7d83a932d0356 Content-Disposition: form-data; name="__LASTFOCUS" -----------------------------7d83a932d0356 Content-Disposition: form-data; name="ctl00_PageContentUser_treeVwPpl_ExpandState" ecnnneennen -----------------------------7d83a932d0356 Content-Disposition: form-data; name="ctl00_PageContentUser_treeVwPpl_SelectedNode" ctl00_PageContentUser_treeVwPplt7 -----------------------------7d83a932d0356 Content-Disposition: form-data; name="ctl00_PageContentUser_treeVwPpl_PopulateLog" -----------------------------7d83a932d0356 Content-Disposition: form-data; name="__VIEWSTATE" +I86gZ1cQhEo5gOTI3hQYjGSfGlmykvtn5+pLgxc/NMWFSKOLc3kONI5pqe8MTjCSQl1c...

...and so on.

I don't know what's going on, and it's drivin' me crazy.

Could anyone help?

Thanks in advance