-debug with -srv causes a panic

[tomsteele]

$ ./blacksheepwall -debug -domain github.com -srv
2015/01/18 05:21:55 Spreading tasks across 100 goroutines
panic: runtime error: index out of range

goroutine 5 [running]:
main.func·002()
/Users/tsteele/code/go/src/github.com/tomsteele/blacksheepwall/blacksheepwall.go:240 +0x548
created by main.main
/Users/tsteele/code/go/src/github.com/tomsteele/blacksheepwall/blacksheepwall.go:246 +0x1c18

goroutine 1 [chan receive]:
main.main()
/Users/tsteele/code/go/src/github.com/tomsteele/blacksheepwall/blacksheepwall.go:351 +0x2e50

goroutine 105 [chan receive]:
main.func·003()
/Users/tsteele/code/go/src/github.com/tomsteele/blacksheepwall/blacksheepwall.go:251 +0xa3
created by main.main
/Users/tsteele/code/go/src/github.com/tomsteele/blacksheepwall/blacksheepwall.go:281 +0x1d7b