Updates are currently disallowed on GET requests

Hi,

i need some assitance with the following problem. In a webapp, which does
some list manipulation eg. delete i get the following error when calling the
delete or update method of a list, but only when the current user is not an
administrator.

Error : Updates are currently disallowed on GET requests. To allow updates
on a GET, set the 'AllowUnsafeUpdates' property on SPWeb.

As you can see from the below code, I have set the AllowUnsafeUpdates
Property. I don't really belive that this has anything to do with get or
post, but more with access rights..

thanks and regards
karsten



Code:
public bool Delete()
{
this.myWeb.AllowUnsafeUpdates = true;
try
{
foreach (SPListItem item in _srSignatures.Values)
{ // exception is thrown on the first item here..
item.ParentList.Items.DeleteItemById(item.ID);
}
File.Item.ParentList.Items.DeleteItemById(File.Item.ID);
_signRequests.Items.DeleteItemById(_liSignRequest.ID);
}
finally
{
this.myWeb.AllowUnsafeUpdates = false;
}
return true;
}
The Url to webapp could be the following:
http://mucc23/sites/ECRv2/_layouts/signRequests/DeleteSignRequest.aspx?sr_id=59&returnUrl=http://mucc23/sites/ECRv2/Views/AllSignRequests.aspx

The assembly of the webapp is in the assembly cache.