diff --git a/README.md b/README.md
index 1c4e706..178113a 100644
--- a/README.md
+++ b/README.md
@@ -55,4 +55,5 @@ Container images are configured using parameters passed at runtime.
 |-e BITMESSAGE_SEED_ADDRESSES|Number of Deterministic Addresses to generate. Default: `1`|
 |-e BITMESSAGE_TTL|The expiration of newly send messages, in seconds. Default: `172800`|
 |-e BITMESSAGE_STOPRESENDINGAFTERXDAYS|Stop resending unreceived message after X days. Default: `60`|
+|-e BITMESSAGE_APIVARIANT|provides xml or json-RPC API. Default: `legacy`|
 
diff --git a/docker/run.sh b/docker/run.sh
index 2d2efe9..741e06e 100644
--- a/docker/run.sh
+++ b/docker/run.sh
@@ -6,6 +6,7 @@ export BITMESSAGE_SEED_ADDRESSES=${BITMESSAGE_SEED_ADDRESSES:-1}
 export BITMESSAGE_API_PORT=${BITMESSAGE_API_PORT:-8442}
 export BITMESSAGE_TTL=${BITMESSAGE_TTL:-172800}
 export BITMESSAGE_STOPRESENDINGAFTERXDAYS=${BITMESSAGE_STOPRESENDINGAFTERXDAYS:-30}
+export BITMESSAGE_APIVARIANT=${BITMESSAGE_APIVARIANT:-legacy}
 
 SEED_FILE="address_seed.txt"
 test -e "$SEED_FILE" || gosu bitmessage touch "$SEED_FILE"
@@ -28,7 +29,7 @@ chmod 600 keys.dat
 
 # set config values
 gosu bitmessage sed -i -e "s|\(apiinterface = \).*|\10\.0\.0\.0|g" \
-	-e "s|\(apivariant = \).*|\1legacy|g" \
+	-e "s|\(apivariant = \).*|\1$BITMESSAGE_APIVARIANT|g" \
 	-e "s|\(apiusername = \).*|\1$BITMESSAGE_API_USER|g" \
 	-e "s|\(apipassword = \).*|\1$BITMESSAGE_API_PASSWORD|g" \
 	-e "s|\(apiport = \).*|\1$BITMESSAGE_API_PORT|g" \