I'm getting a lot of these errors in my logs right now. I'm not sure what queryModified means

Sat Dec 1 01:24:33 [conn117] queryModified:

{ _id: "1353801600day-078041a3b19f83b484f993b6e2b70e3c" }

Sat Dec 1 01:24:33 [conn130] queryModified:

{ _id: "1353783600hour-e47683d0d179af6c7646d1838d55f03d" }

Sat Dec 1 01:24:33 [conn117] queryModified:

{ _id: "1353801600day-8517d74cd492be36d847ae70d6da52a4" }

Sat Dec 1 01:24:33 [conn130] queryModified:

{ _id: "1353780000hour-bc8ae82e1eff03948da1efaec4f37d35" }

Sat Dec 1 01:24:34 [conn117] queryModified:

{ _id: "1353855600hour-eaa54179ff3f15a4003ccd29f7865946" }

Sat Dec 1 01:24:34 [conn130] queryModified:

{ _id: "1351728000month-81b4a6fda64983ddd71b204113f90846" }

Sat Dec 1 01:24:34 [conn130] queryModified:

{ _id: "1353776400hour-4a39f94f5a4291ee815b0ed7bf6ffce4" }

Sat Dec 1 01:24:34 [conn117] queryModified:

{ _id: "1353855600hour-befc2f21bece4c34003ba953a8ca2c0a" }

Sat Dec 1 01:24:34 [migrateThread] warning: moveChunkCmd deleted data already in chunk # objects: 498
Sat Dec 1 01:24:35 [conn130] queryModified:

{ _id: "1353715200day-1120c433e9af1f6684fcfd2e53d4f5e4" }

Sat Dec 1 01:24:35 [conn117] queryModified:

{ _id: "1353855600hour-1843ac5ab7307416de9c8344a3c54873" }

Sat Dec 1 01:24:35 [migrateThread] Assertion: 16333:field names of bound

{ _id: ObjectId('50b93eac6a21db0561007b59') }

do not match those of keyPattern

{ files_id: 1, n: 1 }

0xade6e1 0x8036eb 0x80386c 0x8acb43 0x8ad8f5 0xa28dda 0xa2fd4b 0xa233da 0x7c3659 0x7f418d0daefc 0x7f418c46c59d
/usr/bin/mongod(_ZN5mongo15printStackTraceERSo+0x21) [0xade6e1]
/usr/bin/mongod(_ZN5mongo11msgassertedEiPKc+0x9b) [0x8036eb]
/usr/bin/mongod() [0x80386c]
/usr/bin/mongod(_ZN5mongo7Helpers18modifiedRangeBoundERKNS_7BSONObjES3_i+0x623) [0x8acb43]
/usr/bin/mongod(_ZN5mongo7Helpers11removeRangeERKSsRKNS_7BSONObjES5_S5_bbPNS0_14RemoveCallbackEb+0x765) [0x8ad8f5]
/usr/bin/mongod(_ZN5mongo13MigrateStatus5applyERKNS_7BSONObjEPy+0x2fa) [0xa28dda]
/usr/bin/mongod(_ZN5mongo13MigrateStatus3_goEv+0x294b) [0xa2fd4b]
/usr/bin/mongod(_ZN5mongo13migrateThreadEv+0xca) [0xa233da]
/usr/bin/mongod() [0x7c3659]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x7efc) [0x7f418d0daefc]
/lib/x86_64-linux-gnu/libc.so.6(clone+0x6d) [0x7f418c46c59d]
Sat Dec 1 01:24:35 [migrateThread] scoped connection to mongo2.foobar.com:27018 not being returned to the pool
Sat Dec 1 01:24:35 [migrateThread] about to log metadata event: { _id: "mongo1-2012-12-01T01:24:35-213", server: "mongo1", clientAddr: ":27017", time: new Date(1354325075900), what: "moveChunk.to", ns: "pb3.bloomfilters.chunks", details: { min:

{ files_id: ObjectId('506252d9ebad64296b95b0d5') }

, max:

{ files_id: ObjectId('5062538eebad64296b95c167') }

, step1 of 5: 100, step2 of 5: 3246, step3 of 5: 1512, note: "aborted" } }
Sat Dec 1 01:24:36 [migrateThread] ERROR: migrate failed: field names of bound

{ _id: ObjectId('50b93eac6a21db0561007b59') }

do not match those of keyPattern

{ files_id: 1, n: 1 }

Sat Dec 1 01:24:36 [conn117] queryModified:

{ _id: "1353852000hour-639bf6d6a7c286abea6780eb1857ace3" }

Sat Dec 1 01:24:36 [conn130] queryModified:

{ _id: "1353783600hour-80ec2c441497a8420534c69b1df373bc" }

Sat Dec 1 01:24:36 [conn130] queryModified:

{ _id: "1351728000month-56175f96529db518ec00ba7bbe4d9ef9" }

Sat Dec 1 01:24:36 [conn117] queryModified:

{ _id: "1353852000hour-28f2bebc2006266387995711aa39fd87" }

Sat Dec 1 01:24:36 [conn117] queryModified:

{ _id: "1353855600hour-bd40eb6a4b3b2399bcf495f8aab2b7c9" }

Sat Dec 1 01:24:37 [conn117] queryModified:

{ _id: "1353852000hour-41cb8fb819b94f02b37be027bee14452" }

Sat Dec 1 01:24:37 [conn130] queryModified:

{ _id: "1353783600hour-ed2998e594b023b6fab1f1d2d8a1f86d" }