A common approach for modeling two phase flows is via sharp-interface models. It is known, that here multiple sources of singularities at the three phase contact-line exist. For example the well known results regarding the no-slip boundary condition. In this work we want to analyze a different source of such singularities. To correctly model the dynamic contact angle one idea is to introduce a contact-line force as a function of contact-line velocity , contact angle and equilibrium contact angle as a line force into the Stokes equation. In this work we want to demonstrate the suitability of this approach within our eXtended Discontinuous Galerkin (XDG) method to display a variety of contact-line behaviors, like contact angle hysteresis. However, introducing such line forces into the Stokes system is known to produce singularities at the line of attack. The second part of this work therefore investigates this issue and eliminates these singularities, using a local viscosity model.