The momentum equations in the Brinkman Equations interface and the Free and Porous Media Flow interface have been corrected. The term −Qbr·u/εp2 on the right-hand side previously lacked the factor 1/εp2, where εp is the porosity.In physics interfaces modeling migration (for example, Transport of Diluted Species), anisotropic mobility is now supported, and the mobility can be set to follow the Nernst-Einstein relation. The default setting when making new models has been changed to the Nernst-Einstein relation. Model files for Java®-generated prior to 4.3b using migration will have to be modified manually to account for these changes.