diff --git a/src/common/gamecode/study.c b/src/common/gamecode/study.c
index f0a2cb2bf..ef15e7faf 100644
--- a/src/common/gamecode/study.c
+++ b/src/common/gamecode/study.c
@@ -291,7 +291,7 @@ teach(region * r, unit * u)
 						for (i=0;teachskill[i]!=NOSKILL;++i) if (sk==teachskill[i]) break;
 						sk = teachskill[i];
 					}
-					if (sk != NOSKILL && eff_skill(u, sk, r) > eff_skill(student, sk, r)) {
+					if (sk != NOSKILL && eff_skill_study(u, sk, r)-TEACHDIFFERENCE > eff_skill_study(student, sk, r)) {
 						teaching -= teach_unit(u, student, teaching, sk, true, &academy);
 					}
 				}
@@ -304,7 +304,7 @@ teach(region * r, unit * u)
 				if (igetkeyword(student->thisorder, student->faction->locale) == K_STUDY) {
 					/* Input ist nun von student->thisorder !! */
 					sk = getskill(student->faction->locale);
-					if (sk != NOSKILL && eff_skill(u, sk, r)-TEACHDIFFERENCE >= eff_skill(student, sk, r)) {
+					if (sk != NOSKILL && eff_skill_study(u, sk, r)-TEACHDIFFERENCE >= eff_skill(student, sk, r)) {
 						teaching -= teach_unit(u, student, teaching, sk, true, &academy);
 					}
 				}
@@ -407,7 +407,7 @@ teach(region * r, unit * u)
 			continue;
 		}
 		/* u is teacher, u2 is student */
-		if (eff_skill(u2, sk, r) > eff_skill(u, sk, r)-TEACHDIFFERENCE) {
+		if (eff_skill_study(u2, sk, r) > eff_skill_study(u, sk, r)-TEACHDIFFERENCE) {
 			add_message(&u->faction->msgs,
 				msg_error(u, u->thisorder, "teach_asgood", "student", u2));
 			continue;
diff --git a/src/common/kernel/reports.c b/src/common/kernel/reports.c
index 2c6eb5624..631ba0fc0 100644
--- a/src/common/kernel/reports.c
+++ b/src/common/kernel/reports.c
@@ -633,7 +633,7 @@ spskill(const struct locale * lang, const struct unit * u, skill_t sk, int *dh,
 		int diff;
 
 		if(skill->old > 0) {
-			oldeff = skill->old + get_modifier(u, sk, skill->old, u->region);
+			oldeff = skill->old + get_modifier(u, sk, skill->old, u->region, false);
 		}
 
 		oldeff = max(0, oldeff);
diff --git a/src/common/kernel/unit.c b/src/common/kernel/unit.c
index 0a5f7deae..7bdbe6277 100644
--- a/src/common/kernel/unit.c
+++ b/src/common/kernel/unit.c
@@ -963,8 +963,7 @@ item_modification(const unit *u, skill_t sk, int val)
 	/* Presseausweis: *2 Spionage, 0 Tarnung */
 	if(sk == SK_SPY && get_item(u, I_PRESSCARD) >= u->number) {
 		val = val * 2;
-	}
-	if(sk == SK_STEALTH) {
+	} else if(sk == SK_STEALTH) {
 #if NEWATSROI == 1
 		if(get_item(u, I_RING_OF_INVISIBILITY)
 				+ 100 * get_item(u, I_SPHERE_OF_INVISIBILITY) >= u->number) {
@@ -1031,7 +1030,7 @@ att_modification(const unit *u, skill_t sk)
 }
 
 int
-get_modifier(const unit * u, skill_t sk, int level, const region * r)
+get_modifier(const unit *u, skill_t sk, int level, const region *r, boolean noitem)
 {
 	int bskill = level;
 	int skill = bskill;
@@ -1042,7 +1041,9 @@ get_modifier(const unit * u, skill_t sk, int level, const region * r)
 	skill += rc_skillmod(u->race, r, sk);
 	skill += att_modification(u, sk);
 
-	skill = item_modification(u, sk, skill);
+	if(noitem == false) {
+		skill = item_modification(u, sk, skill);
+	}
 	skill = skillmod(u->attribs, u, r, sk, skill, SMF_ALWAYS);
 
 	if (fspecial(u->faction, FS_TELEPATHY)) {
@@ -1072,7 +1073,19 @@ eff_skill(const unit * u, skill_t sk, const region * r)
 {
 	int level = get_level(u, sk);
 	if (level>0) {
-		int mlevel = level + get_modifier(u, sk, level, r);
+		int mlevel = level + get_modifier(u, sk, level, r, false);
+
+		if (mlevel>0) return mlevel;
+	}
+	return 0;
+}
+
+int
+eff_skill_study(const unit * u, skill_t sk, const region * r)
+{
+	int level = get_level(u, sk);
+	if (level>0) {
+		int mlevel = level + get_modifier(u, sk, level, r, true);
 
 		if (mlevel>0) return mlevel;
 	}
diff --git a/src/common/kernel/unit.h b/src/common/kernel/unit.h
index d99f55849..c84957181 100644
--- a/src/common/kernel/unit.h
+++ b/src/common/kernel/unit.h
@@ -120,7 +120,9 @@ extern int get_level(const struct unit * u, skill_t id);
 extern void transfermen(struct unit * u, struct unit * u2, int n);
 
 extern int eff_skill(const struct unit * u, skill_t sk, const struct region * r);
-extern int get_modifier(const struct unit * u, skill_t sk, int lvl, const struct region * r);
+extern int eff_skill_study(const struct unit * u, skill_t sk, const struct region * r);
+
+extern int get_modifier(const struct unit * u, skill_t sk, int lvl, const struct region * r, boolean noitem);
 
 #undef DESTROY