A conversation with Jonathan Gibbons concluded:
- explicit VM options on the command line get passed to both
  the java VM and the javac VM

- options specified in -vmoption(s) get passed to the java VM
  but not to the javac VM

- options specified in -javacoption(s) get passed to the javac VM
  but not to the java VM

So the bug is that currently, an option specified in -vmoption(s) incorrectly gets passed to javac

The following script demonstrates this. It passes -Xcomp and -showversion in -vmoptions and then shows that the compile is done in 'compiled mode':

#!/bin/sh

JAVA_HOME=/java/re/jdk/1.7.0/latest/binaries/solaris-sparc
export JAVA_HOME
rm -rf /tmp/BB

 ksh /java/re/jct-tools/3.2.2_02/nightly/binaries/latest/solaris/bin/jtreg \
   -a \
   -vmoption:-showversion \
   -vmoption:-Xcomp \
   -othervm -testjdk:$JAVA_HOME \
   -v \
   -w:/tmp/BB \
   -r:/tmp/BB \
   /java/svc/ws/j2se/service_sdk_baseline/test/com/sun/jdi/DeleteAllBkptsTest.java

echo
echo "========================================================"
echo "Note that the compile is done with -Xcomp"
echo "========================================================"

tail -47 /tmp/BB/com/sun/jdi/DeleteAllBkptsTest.jtr | head -14