calling nextval function

Does anybody know how to get the next value of a sequence?

I'm presuming that nextval is an SQL procedure in postgres which can be
called by passing the name of the sequence as a parameter. The code
below shows what I've done in VB. This does not work however - JET
throws up an error saying that 'nextval' table or query cannot be found.

Dim objCmd As New ADODB.Command

Dim objPrm As ADODB.Parameter

objCmd.ActiveConnection = CurrentProject.Connection

objCmd.CommandType = adCmdStoredProc

objCmd.CommandText = "nextval"

Set objPrm = objCmd.CreateParameter("@name", adBSTR, adParamInput, ,
"bed_id_seq")

objCmd.parameters.Append objPrm

Set sequenceNumber = objCmd.Execute

seqNum = sequenceNumber!nextval

Can anbody help me with this?

Regards,

Oliver Gosling