Why does the Scala REPL behave this way?

in 2.7, 2.8, and 2.9 alike:

scala> 2
res0: Int = 2

scala> { 2; 3 }
res1: Int = 3

so far so good, but then:

scala> 2; 3

scala> val a = 2; 3
a: Int = 2

Hey REPL, where'd my 3's go?

(Should I open a ticket?)