How 2 access 2 differnt vb6.0 project

Hello,
i am developing a visual basic 6.0 project where I need to access different projects from one projects .let us hav an eg. A,B,C,D are 4 different projects having multiple forms and reports and needed to be access from Project D. ie Project A,B,C must be accessible from project D.
besides that whenever a new projects is open from Project D the first form that appear must be the login form of that projects .
if possible please mail me the solution of this problem as soon as possible.i will be very glad and thank full
thanks in advance
chandan