Incorrect query syntax causes internal error

[sandfox]

While derping about with the Admin interface and exploring queries, I came across this while mistyping a query, while the query was obviously incorrect, it just returned an internal error rather than anything useful.
Not exactly a critical bug, but I'd thought I'd drop it here anyway.

I'm running InfluxDB v0.6.2 (git: 383d79aa5a41b9c9d8b4d2567ce3276189419f64) (leveldb: 1.15) installed via homebrew on OSX 10.9.2

********************************BUG********************************
Database: metrics-test
Query: [select percentile(*,95) from node-mem group by time(60s)]
Error: interface conversion: interface is nil, not *engine.PercentileAggregatorState. Stacktrace: goroutine 54958 [running]:
common.RecoverFunc(0xc21047d696, 0xc, 0xc210ea2e80, 0x38, 0x5da1e78)
    /private/tmp/influxdb-UzZW/influxdb/src/common/recover.go:13 +0x106
runtime.panic(0x444bf80, 0xc210241780)
    /usr/local/Cellar/go/1.2.1/libexec/src/pkg/runtime/panic.c:248 +0x106
engine.(*PercentileAggregator).CalculateSummaries(0xc2108e1300, 0x0, 0x0)
    /private/tmp/influxdb-UzZW/influxdb/src/engine/aggregator.go:785 +0x3a
engine.func·008(0x0, 0x0, 0x0, 0xc210241640, 0x4027389, ...)
    /private/tmp/influxdb-UzZW/influxdb/src/engine/engine.go:479 +0x98
engine.(*Trie).TraverseLevel(0xc2117288a0, 0xffffffffffffffff, 0x5da1a68, 0x1, 0xc211728870)
    /private/tmp/influxdb-UzZW/influxdb/src/engine/trie.go:54 +0x4c
engine.(*Trie).Traverse(0xc2117288a0, 0x5da1a68, 0x8, 0xc2117288c0)
    /private/tmp/influxdb-UzZW/influxdb/src/engine/trie.go:48 +0x3a
engine.(*QueryEngine).calculateSummariesForTable(0xc21009fc40, 0xc213571110, 0x8)
    /private/tmp/influxdb-UzZW/influxdb/src/engine/engine.go:482 +0x7a
engine.(*QueryEngine).runAggrega