diff --git a/jams-ca/pom.xml b/jams-ca/pom.xml
index 482c776327b8b4798d1da988e8300869e4cc287d..741b9e3b0b7fb4bafeca0ad165d1d9582fcd5511 100644
--- a/jams-ca/pom.xml
+++ b/jams-ca/pom.xml
@@ -11,6 +11,11 @@
 
     <artifactId>cryptoengine</artifactId>
     <dependencies>
+        <dependency>
+            <groupId>commons-codec</groupId>
+            <artifactId>commons-codec</artifactId>
+            <version>${commons.codec.version}</version>
+        </dependency>
         <dependency>
             <groupId>net.jami</groupId>
             <artifactId>jams-common</artifactId>
diff --git a/jams-ca/src/main/java/net/jami/jams/ca/workers/csr/builders/UserBuilder.java b/jams-ca/src/main/java/net/jami/jams/ca/workers/csr/builders/UserBuilder.java
index 7da79d586193f49cb1686ba41515edb040e11d83..83b6c4c1dfe285b219fec0acc64a0921e6162542 100644
--- a/jams-ca/src/main/java/net/jami/jams/ca/workers/csr/builders/UserBuilder.java
+++ b/jams-ca/src/main/java/net/jami/jams/ca/workers/csr/builders/UserBuilder.java
@@ -54,6 +54,9 @@ public class UserBuilder {
             KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
             keyPairGenerator.initialize(4096);
             KeyPair keyPair = keyPairGenerator.generateKeyPair();
+
+            user.getX509Fields().setUid(Hex.encodeHexString(MessageDigest.getInstance(MessageDigestAlgorithms.SHA_1).digest(keyPair.getPublic().getEncoded())));
+
             X509v3CertificateBuilder builder = new X509v3CertificateBuilder(
                     new JcaX509CertificateHolder(JamsCA.CA.getCertificate()).getSubject(),
                     new BigInteger(128, new SecureRandom()),