diff --git a/org.adempiere.ui.zk/WEB-INF/src/metainfo/zk/lang-addon.xml b/org.adempiere.ui.zk/WEB-INF/src/metainfo/zk/lang-addon.xml
index 89accd6338..109f703fb7 100644
--- a/org.adempiere.ui.zk/WEB-INF/src/metainfo/zk/lang-addon.xml
+++ b/org.adempiere.ui.zk/WEB-INF/src/metainfo/zk/lang-addon.xml
@@ -48,7 +48,7 @@ Copyright (C) 2007 Ashley G Ramdass (ADempiere WebUI).
 	<javascript-module name="jawwa.atmosphere" version="202102091500"/>
 	<javascript-module name="adempiere.local.storage" version="202011151100"/>
 	<javascript-moudle name="html2canvas" version="1.0.0.rc7"/>
-	<javascript-module name="org.idempiere.commons" version="202012030330"/>
+	<javascript-module name="org.idempiere.commons" version="202105072207"/>
 	<javascript-module name="jquery.maskedinput" version="1.4.1" />
 	<javascript-module name="photobooth"	version="0.7-rsd3" />
 	<javascript-module name="chosenbox" version="202012041500"/>
diff --git a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/component/NumberBox.java b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/component/NumberBox.java
index 3690fe3b98..8d45ef799a 100644
--- a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/component/NumberBox.java
+++ b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/component/NumberBox.java
@@ -137,6 +137,8 @@ public class NumberBox extends Div
 			@Override
 			public void onEvent(Event event) throws Exception {
 				if (btn.getPopup() != null) {
+					// Fill the calculator with the actual value of the field
+					// TODO: this could be made a user preference
 			        String curValue = "";
 					if (decimalBox.getValue() != null) {
 						curValue = decimalBox.getValue().toString();
@@ -146,6 +148,9 @@ public class NumberBox extends Div
 					        String separator = Character.toString(separatorChar);
 					        curValue = curValue.replace(".", separator);
 				        }
+						if ("0".equals(curValue)) {
+							curValue = "";
+						}
 					}
 					String txtCalcId = txtCalc.getId();
 					Clients.evalJavaScript("calc.append('" + txtCalcId + "', '" + curValue + "')");
diff --git a/org.adempiere.ui.zk/WEB-INF/src/web/js/org/idempiere/commons/calc.js b/org.adempiere.ui.zk/WEB-INF/src/web/js/org/idempiere/commons/calc.js
index 072b66942a..d9f48ce218 100644
--- a/org.adempiere.ui.zk/WEB-INF/src/web/js/org/idempiere/commons/calc.js
+++ b/org.adempiere.ui.zk/WEB-INF/src/web/js/org/idempiere/commons/calc.js
@@ -73,10 +73,14 @@ function Calc()
 				var re = new RegExp("[" + separator + "]", "g");
 				value = value.replace(re,'.');
 			}
-			var reclean = new RegExp("[^1234567890+-/*%() ]", "g"); // sanitize
-			value = value.replace(reclean,'');
-			var reperc = new RegExp("[%]", "g"); // percentage
-			value = value.replace(reperc,'/100 ');
+			value = value
+				.replace(/[^1234567890+-/*%() ]/g, '')            // sanitize
+				.replace(/[%]/g, '/100 ')                         // percentage
+					// now replace leading zeroes
+				.replace(/\b0+\b/g, 'z')                          // replace bare zeros with sentinel 
+				.replace(/[1-9\.]0+/g, m => m.replace(/0/g, 'z')) // save these too
+				.replace(/0/g, '')                                // throw away the rest of the zeros
+				.replace(/z/g, '0');                              // turn sentinels back to zeros
 			newValue = value;
 			var result = "" + eval(value);
 			if (separator != '.')