diff --git a/.gitignore b/.gitignore
index d4d4c9e7b..215378e33 100644
--- a/.gitignore
+++ b/.gitignore
@@ -33,3 +33,6 @@ profile.cov
 
 # vagrant
 .vagrant
+
+# tests
+src/.ethereumtest/
diff --git a/src/gethdep_test.go b/src/gethdep_test.go
index 4aa88b6cc..88fb94f0c 100644
--- a/src/gethdep_test.go
+++ b/src/gethdep_test.go
@@ -20,6 +20,7 @@ import (
 // TestAccountBindings makes sure we can create an account and subsequently
 // unlock that account
 func TestAccountBindings(t *testing.T) {
+	rpcport = 8546 // in order to avoid conflicts with running react-native app
 
 	// start geth node and wait for it to initialize
 	go createAndStartNode(".ethereumtest")
@@ -99,6 +100,12 @@ func TestAccountBindings(t *testing.T) {
 		sentinel = 1
 	})
 
+	// try completing non-existing transaction
+	if err := completeTransaction("0x1234512345123451234512345123456123451234512345123451234512345123"); err == nil {
+		t.Errorf("Test failed: error expected and not recieved")
+	}
+
+	// send normal transaction
 	from, err := utils.MakeAddress(accountManager, address1)
 	if err != nil {
 		t.Errorf("Test failed: Could not retrieve account from address: %v", err)
diff --git a/src/main.go b/src/main.go
index e2d3cd3d2..305681b37 100644
--- a/src/main.go
+++ b/src/main.go
@@ -15,9 +15,9 @@ import (
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/release"
 	"github.com/ethereum/go-ethereum/rlp"
+	"github.com/ethereum/go-ethereum/rpc"
 	"github.com/ethereum/go-ethereum/whisper"
 	"gopkg.in/urfave/cli.v1"
-	"github.com/ethereum/go-ethereum/rpc"
 )
 
 const (
@@ -31,15 +31,16 @@ const (
 )
 
 var (
-	vString        string             // Combined textual representation of the version
-	rConfig        release.Config     // Structured version information and release oracle config
-	currentNode    *node.Node         // currently running geth node
-	c              *cli.Context       // the CLI context used to start the geth node
-	accountSync    *[]node.Service    // the object used to sync accounts between geth services
-	lightEthereum  *les.LightEthereum // LES service
-	accountManager *accounts.Manager  // the account manager attached to the currentNode
-	whisperService *whisper.Whisper   // whisper service
-	datadir        string             // data directory for geth
+	vString        string                    // Combined textual representation of the version
+	rConfig        release.Config            // Structured version information and release oracle config
+	currentNode    *node.Node                // currently running geth node
+	c              *cli.Context              // the CLI context used to start the geth node
+	accountSync    *[]node.Service           // the object used to sync accounts between geth services
+	lightEthereum  *les.LightEthereum        // LES service
+	accountManager *accounts.Manager         // the account manager attached to the currentNode
+	whisperService *whisper.Whisper          // whisper service
+	datadir        string                    // data directory for geth
+	rpcport        int                = 8545 // RPC port (replaced in unit tests)
 	client         rpc.Client
 )
 
@@ -63,7 +64,7 @@ func MakeNode(inputDir string) *node.Node {
 	set.Bool("testnet", true, "light test network")
 	set.Bool("rpc", true, "enable rpc")
 	set.String("rpcaddr", "localhost", "host for RPC")
-	set.String("rpcport", "8545", "rpc port")
+	set.Int("rpcport", rpcport, "rpc port")
 	set.String("rpccorsdomain", "*", "allow all domains")
 	set.String("verbosity", "3", "verbosity level")
 	set.String("rpcapi", "db,eth,net,web3,shh,personal,admin", "rpc api(s)")
diff --git a/src/vendor/github.com/ethereum/go-ethereum/les/status_backend.go b/src/vendor/github.com/ethereum/go-ethereum/les/status_backend.go
index 90ce704a8..ad81891f6 100644
--- a/src/vendor/github.com/ethereum/go-ethereum/les/status_backend.go
+++ b/src/vendor/github.com/ethereum/go-ethereum/les/status_backend.go
@@ -9,11 +9,18 @@ import (
 	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/logger/glog"
 	"github.com/ethereum/go-ethereum/rpc"
+	"errors"
 )
 
-const defaultTxQueueCap = int(5)
-const defaultEvictingTxQueueCap = int(20)
-const defaultEvictingTxQueueEvictionStep = int(5) // how many item to evict in a single run
+const (
+	defaultTxQueueCap                  = int(5)  // how many items can be passed to sendTransaction() w/o blocking
+	defaultEvictingTxQueueCap          = int(20) // how many items can be queued
+	defaultEvictingTxQueueEvictionStep = int(5)  // how many item to evict in a single run
+)
+
+var (
+	ErrQueuedTxHashNotFound = errors.New("Transaction hash not found")
+)
 
 // StatusBackend implements les.StatusBackend with direct calls to Ethereum
 // internals to support calls from status-go bindings (to internal packages e.g. ethapi)
@@ -113,7 +120,7 @@ func (b *StatusBackend) GetTransactionQueue() (chan QueuedTx, error) {
 func (b *StatusBackend) transactionQueueForwardingLoop() {
 	txQueue, err := b.txapi.GetTransactionQueue()
 	if err != nil {
-		glog.V(logger.Error).Infof("Cannot read from transaction queue")
+		glog.V(logger.Error).Infof("cannot read from transaction queue")
 		return
 	}
 
@@ -158,5 +165,5 @@ func (q *evictingTxQueue) getQueuedTransaction(hash QueuedTxHash) (*QueuedTx, er
 		return tx, nil
 	}
 
-	return nil, nil
+	return nil, ErrQueuedTxHashNotFound
 }