diff --git a/cmd/mtwebmapper/config.go b/cmd/mtwebmapper/config.go
index 63407c7..f4c5f0a 100644
--- a/cmd/mtwebmapper/config.go
+++ b/cmd/mtwebmapper/config.go
@@ -13,24 +13,34 @@ import (
 	"bitbucket.org/s_l_teichmann/mtsatellite/common"
 )
 
+type duration struct {
+	time.Duration
+}
+
 type config struct {
-	WebPort        int           `toml:"web_port"`
-	WebHost        string        `toml:"web_host"`
-	WebDir         string        `toml:"web"`
-	MapDir         string        `toml:"map"`
-	RedisPort      int           `toml:"redis_port"`
-	RedisHost      string        `toml:"redis_host"`
-	ColorsFile     string        `toml:"update_hosts"`
-	BGColor        string        `toml:"background"`
-	Workers        int           `toml:"workers"`
-	Transparent    bool          `toml:"transparent"`
-	TransparentDim float64       `toml:"transparent_dim"`
-	UpdateHosts    string        `toml:"update_hosts"`
-	Websockets     bool          `toml:"websockets"`
-	PlayersFIFO    string        `toml:"players"`
-	YMin           int           `toml:"ymin"`
-	YMax           int           `toml:"ymax"`
-	ChangeDuration time.Duration `toml:"change_duration"`
+	WebPort        int      `toml:"web_port"`
+	WebHost        string   `toml:"web_host"`
+	WebDir         string   `toml:"web"`
+	MapDir         string   `toml:"map"`
+	RedisPort      int      `toml:"redis_port"`
+	RedisHost      string   `toml:"redis_host"`
+	ColorsFile     string   `toml:"update_hosts"`
+	BGColor        string   `toml:"background"`
+	Workers        int      `toml:"workers"`
+	Transparent    bool     `toml:"transparent"`
+	TransparentDim float64  `toml:"transparent_dim"`
+	UpdateHosts    string   `toml:"update_hosts"`
+	Websockets     bool     `toml:"websockets"`
+	PlayersFIFO    string   `toml:"players"`
+	YMin           int      `toml:"ymin"`
+	YMax           int      `toml:"ymax"`
+	ChangeDuration duration `toml:"change_duration"`
+}
+
+func (d *duration) UnmarshalText(text []byte) error {
+	var err error
+	d.Duration, err = time.ParseDuration(string(text))
+	return err
 }
 
 func (cfg *config) bindFlags() {
@@ -71,7 +81,7 @@ func (cfg *config) bindFlags() {
 	flag.StringVar(&cfg.PlayersFIFO, "ps", "", "Path to FIFO file to read active players from (shorthand).")
 	flag.IntVar(&cfg.YMin, "ymin", common.MinHeight, "Minimum y in blocks.")
 	flag.IntVar(&cfg.YMax, "ymax", common.MaxHeight, "Maximum y in blocks.")
-	flag.DurationVar(&cfg.ChangeDuration,
+	flag.DurationVar(&cfg.ChangeDuration.Duration,
 		"change-duration", time.Second, "Duration to aggregate changes. (PG only)")
 }
 
diff --git a/cmd/mtwebmapper/main.go b/cmd/mtwebmapper/main.go
index 1f4ba41..64c465f 100644
--- a/cmd/mtwebmapper/main.go
+++ b/cmd/mtwebmapper/main.go
@@ -96,7 +96,7 @@ func main() {
 		go tu.doUpdates()
 
 		if pgHost, ok := common.IsPostgreSQL(cfg.RedisHost); btu != nil && ok {
-			go tu.listen(pgHost, cfg.ChangeDuration)
+			go tu.listen(pgHost, cfg.ChangeDuration.Duration)
 		} else {
 			router.Path("/update").Methods("POST").Handler(tu)
 		}