Conclusions MMC e+- pair production cross section was corrected. It was underestimated by 5%, which led to a ~3% error in propagation of 100 TeV muons. MUM 8-point integration used for e+- cross section has an insufficient precision. ABB and KKP bremsstrahlung cross section parameterizations differ for hydrogen. KKP is used in AMANDA and the most recent. All cross sections now agree between MMC and MUM, and differences can be explained.