diff --git a/htdocs/install/mysql/migration/3.6.0-3.7.0.sql b/htdocs/install/mysql/migration/3.6.0-3.7.0.sql
index e4fbcfbec9a..de02887abf8 100755
--- a/htdocs/install/mysql/migration/3.6.0-3.7.0.sql
+++ b/htdocs/install/mysql/migration/3.6.0-3.7.0.sql
@@ -27,6 +27,11 @@ insert into llx_c_action_trigger (code,label,description,elementtype,rang) value
 insert into llx_c_action_trigger (code,label,description,elementtype,rang) values ('FICHINTER_REOPEN','Intervention opened','Executed when a intervention is re-opened','ficheinter',19);
 insert into llx_c_action_trigger (code,label,description,elementtype,rang) values ('PROPAL_CLASSIFY_BILLED','Customer proposal set billed','Executed when a customer proposal is set to billed','propal',2);
 
+-- VPGSQL8.2 ALTER TABLE llx_contrat ALTER COLUMN fk_commercial_signature DROP NOT NULL;
+-- VPGSQL8.2 ALTER TABLE llx_contrat ALTER COLUMN fk_commercial_suivi DROP NOT NULL;
+ALTER TABLE llx_contrat MODIFY fk_commercial_signature integer NULL;
+ALTER TABLE llx_contrat MODIFY fk_commercial_suivi integer NULL;
+
 ALTER TABLE llx_notify ADD COLUMN fk_soc integer NULL after fk_action;
 ALTER TABLE llx_notify ADD COLUMN type varchar(16) DEFAULT 'email' after fk_soc;
 
diff --git a/htdocs/install/mysql/tables/llx_contrat.sql b/htdocs/install/mysql/tables/llx_contrat.sql
index 4631b660d46..5efbcdfe1fa 100644
--- a/htdocs/install/mysql/tables/llx_contrat.sql
+++ b/htdocs/install/mysql/tables/llx_contrat.sql
@@ -33,8 +33,8 @@ create table llx_contrat
   date_cloture				datetime,
   fk_soc					integer NOT NULL,
   fk_projet					integer,
-  fk_commercial_signature	integer NOT NULL, -- obsolete
-  fk_commercial_suivi 		integer NOT NULL,	-- obsolete
+  fk_commercial_signature	integer, -- obsolete
+  fk_commercial_suivi 		integer, -- obsolete
   fk_user_author			integer NOT NULL default 0,
   fk_user_mise_en_service	integer,
   fk_user_cloture			integer,