diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7b84498..9236ee3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,8 +3,8 @@ project (dublin-traceroute)
 
 # TODO sync this with VERSION in include/dublintraceroute/common.h
 set (dublin-traceroute_VERSION_MAJOR_0)
-set (dublin-traceroute_VERSION_MINOR_3)
-set (dublin-traceroute_VERSION_PATCH_3)
+set (dublin-traceroute_VERSION_MINOR_4)
+set (dublin-traceroute_VERSION_PATCH_0)
 
 # ensure that /usr/local is used to find dependencies. This is especially
 # necessary for brew on OSX and for libraries installed manually under
@@ -25,7 +25,7 @@ add_library(dublintraceroute SHARED
 # Set the shared library version
 set_target_properties(dublintraceroute
     PROPERTIES
-      SOVERSION 0.0.1
+      SOVERSION 0.1.0
     )
 
 find_package(PkgConfig)
diff --git a/documentation/readme/README.md b/documentation/readme/README.md
index f63c25f..de8a180 100644
--- a/documentation/readme/README.md
+++ b/documentation/readme/README.md
@@ -220,7 +220,7 @@ The usage is very simple, and explained in the help message:
 
 ```bash
 $ ./dublin-traceroute --help
-Dublin Traceroute
+Dublin Traceroute v0.3.3
 Written by Andrea Barberio - https://insomniac.slackware.it
 
 Usage:
@@ -229,6 +229,7 @@ Usage:
                              [--npaths=num_paths]
                              [--min-ttl=min_ttl]
                              [--max-ttl=max_ttl]
+                             [--delay=delay_in_ms]
                              [--broken-nat]
                              [--help]
                              [--version]
@@ -239,8 +240,9 @@ Options:
   -s SRC_PORT --sport=SRC_PORT  the source port to send packets from
   -d DST_PORT --dport=DST_PORT  the base destination port to send packets to
   -n NPATHS --npaths=NPATHS     the number of paths to probe
-  -t MIN_TTL --min-ttl=MIN_TTL  the MINIMUM TTL to probe. Must be greater or equal than the minimum TTL
-  -T MAX_TTL --max-ttl=MAX_TTL  the maximum TTL to probe
+  -t MIN_TTL --min-ttl=MIN_TTL  the minimum TTL to probe
+  -T MAX_TTL --max-ttl=MAX_TTL  the maximum TTL to probe. Must be greater or equal than the minimum TTL
+  -D DELAY --delay=DELAY        the inter-packet delay
   -b --broken-nat               the network has a broken NAT configuration (e.g. no payload fixup). Try this if you see less hops than expected
 
 
diff --git a/include/dublintraceroute/common.h b/include/dublintraceroute/common.h
index 15d07b0..7f6cff8 100644
--- a/include/dublintraceroute/common.h
+++ b/include/dublintraceroute/common.h
@@ -16,7 +16,7 @@
 #ifndef _COMMON_H
 #define _COMMON_H
 
-#define VERSION	"0.3.3"
+#define VERSION	"0.4.0"
 
 #include <map>
 
diff --git a/src/main.cc b/src/main.cc
index ba21bfe..8fe998f 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -31,8 +31,8 @@ const struct option longopts[] = {
 
 static void usage() {
 	std::cout <<
-R"(Dublin Traceroute
-Written by Andrea Barberio - https://insomniac.slackware.it
+"Dublin Traceroute v" VERSION "\n"
+R"(Written by Andrea Barberio - https://insomniac.slackware.it
 
 Usage:
   dublin-traceroute <target> [--sport=SRC_PORT]