Those sorts of java runtime errors largely depend on programmers' insistence on doing things via reflection, and it will be the same in any programming language: Like most drugs, at first reflection seems you've opened a new door into enlightenment, until eventually you find yourself sleeping in a gutter with half your teeth missing and wondering why it didn't work out as expected. A lot of Java open source is addicted to this stuff.

Scala just adds more drugs to the cocktail.