ms sql server 1251 -> unicode

zdraweite,
imam sledniqt problem
mssql server, db s poleta nvarchar, no v poletata ima kirilica 1251
ideqta e taz kirilica da se oburne v unicode po lesniq nachin.. moga da go obyrna na 1251 prez .net application (select -> blabla.convert-> update, no me interesuva dali ima nqkakuv sql nachin da stane tova.
t.e. neshto ot sorta:
update table set field=neshto_1251_to_uniciode(field)
(collate i cast neshto ne mi pomagat ili az byrkam sintaksisa)
namerih nqkakva dll na ms ([линк]), no mi dava greshka sled kato loadna controla (dts: no such interface)
idei?

pa da vzema pak sam da si otgovorq.. dano e ot polza i na drugi:

CREATE FUNCTION tounicode (@s nvarchar(200))  

RETURNS nvarchar(200)  AS  

BEGIN 



declare @p int

declare @len int

declare @r nvarchar(200)

declare @c nchar



set @p = 1

set @r = N''

set @len = len(@s)



while @p<=@len

    begin

    set @c = substring(@s,@p,1)

    if unicode(@c)<128

        set @r = @r + @c

	else

        set @r= @r +  nchar(848+unicode(@c))

    set @p = @p+1

    end

return @r

END