What's wrong in the following sql query?

SELECT spomast.matcode, partmast.DESCRIPT, spomast.spono, procmast.DESCRIPTIO, ;
	spomast.sporate, spomast.maincode FROM spomast inner JOIN accmst ON spomast.maincode = accmst.maincode ;
	inner JOIN procmast oN spomast.proccode = procmast.proccode ;
	inner JOIN partmast ON spomast.matcode = partmast.partno where spomast.maincode = '136S05'

with this query no records are selected - where as if "where" clause is removed all records are selected.

Ulhas Amrite