$not expression inside $elemMatch causes assertion error

 { a: { $elemMatch: { $gt:4, $not: { $gte:6 } } } } 

Assertion failure 0 src/mongo/db/query/index_bounds_builder.cpp 447

0x10063f1fb 0x1005f7fc2 0x1005e8a12 0x10037aaa7 0x100379256 0x10039cfd8 0x10039da8b 0x1003a92c8 0x100370306 0x100370f2e 0x1002b25cd 0x10019dd04 0x100198ba5 0x1001997fd 0x10019a41c 0x100386573 0x1002630f6 0x100006f24 0x1006056b1 0x100673e55 

 0   mongod                              0x000000010063f1fb _ZN5mongo15printStackTraceERSo + 43

 1   mongod                              0x00000001005f7fc2 _ZN5mongo10logContextEPKc + 114

 2   mongod                              0x00000001005e8a12 _ZN5mongo12verifyFailedEPKcS1_j + 274

 3   mongod                              0x000000010037aaa7 _ZN5mongo18IndexBoundsBuilder9translateEPKNS_15MatchExpressionERKNS_11BSONElementERKNS_10IndexEntryEPNS_19OrderedIntervalListEPNS0_15BoundsTightnessE + 6605

 4   mongod                              0x0000000100379256 _ZN5mongo18IndexBoundsBuilder9translateEPKNS_15MatchExpressionERKNS_11BSONElementERKNS_10IndexEntryEPNS_19OrderedIntervalListEPNS0_15BoundsTightnessE + 380

 5   mongod                              0x000000010039cfd8 _ZN5mongo18QueryPlannerAccess12makeLeafNodeERKNS_14CanonicalQueryERKNS_10IndexEntryEPNS_15MatchExpressionEPNS_18IndexBoundsBuilder15BoundsTightnessE + 1984

 6   mongod                              0x000000010039da8b _ZN5mongo18QueryPlannerAccess22buildIndexedDataAccessERKNS_14CanonicalQueryEPNS_15MatchExpressionEbRKSt6vectorINS_10IndexEntryESaIS7_EE + 285

 7   mongod                              0x00000001003a92c8 _ZN5mongo12QueryPlanner4planERKNS_14CanonicalQueryERKNS_18QueryPlannerParamsEPSt6vectorIPNS_13QuerySolutionESaIS9_EE + 9246

 8   mongod                              0x0000000100370306 _ZN5mongo9getRunnerEPNS_10CollectionEPNS_14CanonicalQueryEPPNS_6RunnerEm + 3094

 9   mongod                              0x0000000100370f2e _ZN5mongo9getRunnerEPNS_14CanonicalQueryEPPNS_6RunnerEm + 158

 10  mongod                              0x00000001002b25cd _ZN5mongo8runCountERKSsRKNS_7BSONObjERSsRi + 1485

 11  mongod                              0x000000010019dd04 _ZN5mongo8CmdCount3runERKSsRNS_7BSONObjEiRSsRNS_14BSONObjBuilderEb + 296

 12  mongod                              0x0000000100198ba5 _ZN5mongo12_execCommandEPNS_7CommandERKSsRNS_7BSONObjEiRSsRNS_14BSONObjBuilderEb + 37

 13  mongod                              0x00000001001997fd _ZN5mongo7Command11execCommandEPS0_RNS_6ClientEiPKcRNS_7BSONObjERNS_14BSONObjBuilderEb + 2593

 14  mongod                              0x000000010019a41c _ZN5mongo12_runCommandsEPKcRNS_7BSONObjERNS_11_BufBuilderINS_16TrivialAllocatorEEERNS_14BSONObjBuilderEbi + 1388

 15  mongod                              0x0000000100386573 _ZN5mongo11newRunQueryERNS_7MessageERNS_12QueryMessageERNS_5CurOpES1_ + 1843

 16  mongod                              0x00000001002630f6 _ZN5mongo16assembleResponseERNS_7MessageERNS_10DbResponseERKNS_11HostAndPortE + 1958

 17  mongod                              0x0000000100006f24 _ZN5mongo16MyMessageHandler7processERNS_7MessageEPNS_21AbstractMessagingPortEPNS_9LastErrorE + 308

 18  mongod                              0x00000001006056b1 _ZN5mongo17PortMessageServer17handleIncomingMsgEPv + 1681

 19  mongod                              0x0000000100673e55 thread_proxy + 229

2014-01-29T14:46:52.282-0500 count failed: {

	"errmsg" : "exception: assertion src/mongo/db/query/index_bounds_builder.cpp:447",

	"code" : 0,

	"ok" : 0

} at src/mongo/shell/query.js:188