tendermint version: 0.23.1-9e940b95

Steps to reproduce:

[vagrant@dev tm-bench]$tm-bench -T 10 -r 10 -s 39 localhost:26657
panic: runtime error: slice bounds out of range

goroutine 13 [running]:
main.generateTx(0x0, 0x0, 0x27, 0xf7ec95a0bcd06a05, 0x11c84eadb4a4a45b, 0x20, 0xc4200fcb00, 0xc420705d58)
/home/vagrant/gocode/src/github.com/tendermint/tendermint/tools/tm-bench/transacter.go:266 +0x263
main.(*transacter).sendLoop(0xc42055ea00, 0x0)
/home/vagrant/gocode/src/github.com/tendermint/tendermint/tools/tm-bench/transacter.go:165 +0x2fb
created by main.(*transacter).Start
/home/vagrant/gocode/src/github.com/tendermint/tendermint/tools/tm-bench/transacter.go:82 +0x186