diff --git a/migration/i1.0a-release/oracle/201304131924_IDEMPIERE-790.sql b/migration/i1.0a-release/oracle/201304131924_IDEMPIERE-790.sql
new file mode 100644
index 0000000000..868e40aca6
--- /dev/null
+++ b/migration/i1.0a-release/oracle/201304131924_IDEMPIERE-790.sql
@@ -0,0 +1,12 @@
+-- Apr 13, 2013 7:23:49 PM COT
+-- IDEMPIERE-790 Voiding PO should unlink SO it was created from
+UPDATE AD_Column SET IsAllowCopy='N',Updated=TO_DATE('2013-04-13 19:23:49','YYYY-MM-DD HH24:MI:SS'),UpdatedBy=100 WHERE AD_Column_ID=55322
+;
+
+-- Apr 13, 2013 7:24:14 PM COT
+UPDATE AD_Column SET IsAllowCopy='N',Updated=TO_DATE('2013-04-13 19:24:14','YYYY-MM-DD HH24:MI:SS'),UpdatedBy=100 WHERE AD_Column_ID=55323
+;
+
+SELECT register_migration_script('201304131924_IDEMPIERE-790.sql') FROM dual
+;
+
diff --git a/migration/i1.0a-release/postgresql/201304131924_IDEMPIERE-790.sql b/migration/i1.0a-release/postgresql/201304131924_IDEMPIERE-790.sql
new file mode 100644
index 0000000000..787f6b8a7c
--- /dev/null
+++ b/migration/i1.0a-release/postgresql/201304131924_IDEMPIERE-790.sql
@@ -0,0 +1,12 @@
+-- Apr 13, 2013 7:23:49 PM COT
+-- IDEMPIERE-790 Voiding PO should unlink SO it was created from
+UPDATE AD_Column SET IsAllowCopy='N',Updated=TO_TIMESTAMP('2013-04-13 19:23:49','YYYY-MM-DD HH24:MI:SS'),UpdatedBy=100 WHERE AD_Column_ID=55322
+;
+
+-- Apr 13, 2013 7:24:14 PM COT
+UPDATE AD_Column SET IsAllowCopy='N',Updated=TO_TIMESTAMP('2013-04-13 19:24:14','YYYY-MM-DD HH24:MI:SS'),UpdatedBy=100 WHERE AD_Column_ID=55323
+;
+
+SELECT register_migration_script('201304131924_IDEMPIERE-790.sql') FROM dual
+;
+
diff --git a/org.adempiere.base/src/org/compiere/model/MOrder.java b/org.adempiere.base/src/org/compiere/model/MOrder.java
index 40c4d3e5e6..6ec34c99e1 100644
--- a/org.adempiere.base/src/org/compiere/model/MOrder.java
+++ b/org.adempiere.base/src/org/compiere/model/MOrder.java
@@ -2401,6 +2401,11 @@ public class MOrder extends X_C_Order implements DocAction
 		if (m_processMsg != null)
 			return false;
 
+		if (getLink_Order_ID() > 0) {
+			MOrder so = new MOrder(getCtx(), getLink_Order_ID(), get_TrxName());
+			so.setLink_Order_ID(0);
+			so.saveEx();
+		}
 		MOrderLine[] lines = getLines(true, MOrderLine.COLUMNNAME_M_Product_ID);
 		for (int i = 0; i < lines.length; i++)
 		{
@@ -2418,6 +2423,11 @@ public class MOrder extends X_C_Order implements DocAction
 			{
 				deleteMatchPOCostDetail(line);
 			}
+			if (line.getLink_OrderLine_ID() > 0) {
+				MOrderLine soline = new MOrderLine(getCtx(), line.getLink_OrderLine_ID(), get_TrxName());
+				soline.setLink_OrderLine_ID(0);
+				soline.saveEx();
+			}
 		}
 		
 		// update taxes