JVM crash when next() over a line of code that throws an exception

[jbalint]

This is happening on MySQL Connector/J 5.1 when debugging ConnectionRegressionTest.testExpiredPassword()

The following line throws an exception:
testConn = getConnectionWithProps(props);

calling next() in YT crashes the JVM

[jbalint]

check that overwriting signal handlers in yt.c is kosher:
Warning: SIGINT handler expected:libjvm.so+0x743b30 found:0x0000000000000001
Signal Handlers:
SIGSEGV: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGBUS: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGFPE: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGPIPE: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGXFSZ: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGILL: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGUSR1: SIG_DFL, sa_mask[0]=0x00000000, sa_flags=0x00000000
SIGUSR2: [libjvm.so+0x7417a0], sa_mask[0]=0x00000000, sa_flags=0x10000004
SIGHUP: [libjvm.so+0x743b30], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGINT: SIG_IGN, sa_mask[0]=0x00000000, sa_flags=0x00000000
SIGTERM: [libjvm.so+0x743b30], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGQUIT: SIG_IGN, sa_mask[0]=0x00000000, sa_flags=0x00000000
Warning: SIGQUIT handler expected:libjvm.so+0x743b30 found:0x0000000000000001
Signal Handlers:
SIGSEGV: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGBUS: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGFPE: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGPIPE: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGXFSZ: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGILL: [libjvm.so+0x741e50], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGUSR1: SIG_DFL, sa_mask[0]=0x00000000, sa_flags=0x00000000
SIGUSR2: [libjvm.so+0x7417a0], sa_mask[0]=0x00000000, sa_flags=0x10000004
SIGHUP: [libjvm.so+0x743b30], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGINT: SIG_IGN, sa_mask[0]=0x00000000, sa_flags=0x00000000
SIGTERM: [libjvm.so+0x743b30], sa_mask[0]=0x7ffbfeff, sa_flags=0x10000004
SIGQUIT: SIG_IGN, sa_mask[0]=0x00000000, sa_flags=0x00000000

[jbalint]

the warning can be squelched with:
export LD_PRELOAD=$JAVA_HOME/jre/lib/amd64/libjsig.so

It's cause remains unknown, Even when I don't modify signal handlers in yt.c