Postgresql with postGIS and entity framework, CHECK constraint issue

I have a postgresql database with postGIS and I'm using entity framework with dotconnect for postgresql 6.7.

I'm running the following code:

    using (testModel.testEntities ctx = new test.testEntities()) {
        var testVar = new testModel.geo();
        testVar.the_geom = DbGeometry.PointFromText("POINT (0 0)", 4326).AsBinary();
        ctx.testGeoms.AddObject(testVar);
        ctx.SaveChanges();
    }

The following constraint fails in the database

CONSTRAINT enforce_srid_the_geom CHECK (st_srid(the_geom) = 4326)

Curious for what value the database registered, I tried having the following two constraints

CONSTRAINT enforce_srid_the_geom CHECK(st_srid(the_geom) > 4326)
CONSTRAINT enforce_srid_the_geom CHECK(st_srid(the_geom) < 4326)

Neither worked. Since these are integer values being compared, atleast one of the last three queries should have been true.

After a while I found that the following constraint lets me insert something with srid=4326 into the table

st_srid(the_geom) <= 4326)

but it seems to accept everything, both larger and smaller srids, for some reason.

Is this a bug in postgresql, entity framework or dotconnect?

Edit: The query

SELECT st_srid(the_geom) FROM geo WHERE geo.id == 0

returns the srid 0. So, no matter what srid I give specify in entity framework, it appears as 0 in the database. What is going on?