Default Sorting a bidirectional one-to-many association fails

I was trying to default sort a bidirectional one-to-many association but it keeps on failing
with error: java.sql.SQLSyntaxErrorException: ORA-00904: "QUESTIONCA3_"."DISPLAY_ORDER": invalid identifier,

I checked the db and DISPLAY_ORDER is there

My Domain classes are as follows

Class Section{
Integer displayOrder

static hasMany=[questionCategories:QuestionCategory]
static mapping=

}

Class QuestionCategory{
Integer displayOrder
static hasMany=[questions:Question]

static mapping=

}

Class Question

I can work this around using SortedSet approach, but unfortunately i cannot use it