updating a linked oracle table from access error

Hi, i've got an oracle db with an access front end. (using an odbc link thingy) and i i've got some vba that runs an sql update statement which is sopose to change all the rows with the PROJ_NO of dblProNo to dblNew

SQL:

UPDATE table1 SET table1.PROJ_NO = " _
& dblNew & " WHERE PROJ_NO Like " & dblProNo


i get the error :

Odbc update on linked table 'table1' failed. [oracle][odbc]Function sequence error(#0)

any ideas why i'm getting this error??