Error on Clustered Index and NText Field

Hi i have a problem whenever i try to update a table in which i have a clustered index and a ntext field i have this error through a ASP page

Microsoft OLE DB Provider for SQL Server (0x80040E14)
The query processor could not produce a query plan from the optimizer because a query cannot update a text, ntext, or image column and a clustering key at the same time.

ThanksMay be you are trying to update more then one recond in query.

BOL:

If an update query could alter more than one row while updating both the clustering key and one or more text, image, or Unicode columns, the update operation fails and SQL Server returns an error message.

Modifying a text, ntext, or image column with UPDATE initializes the column, assigns a valid text pointer to it, and allocates at least one data page unless updating the column with NULL.

Note The UPDATE statement is logged. If you are replacing or modifying large blocks of text, ntext, or image data, use the WRITETEXT or UPDATETEXT statement instead of the UPDATE statement. The WRITETEXT and UPDATETEXT statements (by default) are not logged.|||i only have this error when i try to update the ntext field and the data is > than 10 KB...
Any idea and how could i use the updatetext in a asp SCRIPT?
Thanks again