1) Have you ever had another Eclipse version installed on your machine?
If yes - try to remove ".eclipse" folder from your $HOME directory andthen re-run vtlec with a new workspace.
2) Or you can try to use another JVM for running eclipse:
- download and install 32-bit Sun JRE 1.5
- set environment variable OTHER_JVM_BINDIR=/path/to/sun_jre_1.5/bin
- run vtlec