SET Role doesn't work from Security Definer Function...

Hi,

I have just noticed that "SET ROLE" doesn't work from security definer
function. I don;t know why but it clearly gives the error that SET role
doesn;t work in security definer context.

Basically, I am trying to write a store procedure which creates a table
asked by user along with other associated logging tables and event tables
automatically. I want to make sure that when users use my stored procedure
to create table, they should be allowed only if they have permission to do
so.

If I create function in postgres user with Security Definer enabled, it will
allow to create any table with any foreign references etc...So I am setting
role to current_user in my function and then creating a table to make sure
that user has the appropriate privilege.

Since, SET Role is failing in security definer context, I am helpless now.
Could anyone suggest any workaround or solution to this issue. Is this is
known issue? Anybody already encountered it?

Thanks,
Dipti