bug in package-attribute in interfaces

[Extrawurst]

is this possibly a bug in dmd ?

[CODE FILE "test/inter.d"]
module test.inter;

interface IFoo {
    package void bar();
}

class Foo:IFoo {
    package void bar() {
    }
}

[CODE FILE "test/testMe.d"]
module test.testMe;

import test.inter;

class Test {
    IFoo    member;
    this() {
        member = new Foo();
    }
   
    void bla() {
        member.bar();
    }
}

[CODE FILE "main.d"]
module main;

import test.testMe;

void main(){
    Test test = new Test();

    test.bla();
}

Gives linker error:
test\testMe.obj(testMe)
 Error 42: Symbol Undefined _D4test5inter4IFoo3barMFZv

why is this?