7.5dev assertion failure w/ v3 protocol and transactions

Running the JDBC driver's regression tests I came across an assertion
failure in 7.5dev. The test does:

BEGIN;
SELECT 1/0;
COMMIT;

and gets the following stacktrace. Note this cannot be replicated in psql
because it requires using the extended query protocol.

Kris Jurka

#0 0x402a5721 in kill () from /lib/libc.so.6
#1 0x402a54c5 in raise () from /lib/libc.so.6
#2 0x402a69e8 in abort () from /lib/libc.so.6
#3 0x082313c2 in ExceptionalCondition (
conditionName=0x6 <Address 0x6 out of bounds>,
errorType=0x82546fb "FailedAssertion", fileName=0x403ab550 "`\022",
lineNumber=0) at assert.c:50
#4 0x08247342 in AtCleanup_Portals () at portalmem.c:574
#5 0x080a9336 in CleanupTransaction () at xact.c:1597
#6 0x080a9567 in CommitTransactionCommand () at xact.c:1760
#7 0x081bf024 in finish_xact_command () at postgres.c:1842
#8 0x081beb4f in exec_execute_message (portal_name=0x8377401 "",
max_rows=1)
at postgres.c:1686
#9 0x081c04e2 in PostgresMain (argc=4, argv=0x83329ac,
username=0x83328b8 "test") at postgres.c:3021
#10 0x081917b6 in BackendRun (port=0x833f898) at postmaster.c:2790
#11 0x08191163 in BackendStartup (port=0x833f898) at postmaster.c:2411
#12 0x0818f43a in ServerLoop () at postmaster.c:1198
#13 0x0818e685 in PostmasterMain (argc=3, argv=0x83324b8) at
postmaster.c:885
#14 0x081587d5 in main (argc=3, argv=0x83324b8) at main.c:265