diff --git a/src/ProjLib/ProjLib_Cone.cxx b/src/ProjLib/ProjLib_Cone.cxx
index 005f2e3b80..9118233252 100644
--- a/src/ProjLib/ProjLib_Cone.cxx
+++ b/src/ProjLib/ProjLib_Cone.cxx
@@ -94,10 +94,19 @@ void  ProjLib_Cone::Init(const gp_Cone& Co)
 
 void  ProjLib_Cone::Project(const gp_Lin& L)
 {
+  gp_Pnt aPnt = L.Location(), anApex = myCone.Apex();
+
+  Standard_Real aDeltaV = 0.0;
 
   Standard_Real U,V;
+  if (aPnt.IsEqual(anApex, Precision::Confusion()))
+  {
+    //Take another point in the line L, which does not coincide with the cone apex.
+    aPnt.Translate(L.Direction().XYZ());
+    aDeltaV = 1.0; // == ||L.Direction()|| == 1.0
+  }
  
-  ElSLib::ConeParameters(myCone.Position(), myCone.RefRadius(), myCone.SemiAngle(), L.Location(),
+  ElSLib::ConeParameters(myCone.Position(), myCone.RefRadius(), myCone.SemiAngle(), aPnt,
 			                   U, V);
   //
   gp_Pnt P;
@@ -107,21 +116,19 @@ void  ProjLib_Cone::Project(const gp_Lin& L)
 		 P, Vu, Vv);
 
   gp_Dir Dv(Vv);
-  if(Dv.IsParallel(L.Direction(), Precision::Angular())) {
-
+  if(Dv.IsParallel(L.Direction(), Precision::Angular()))
+  {
+    // L is parallel to U-isoline of the cone.
     myType = GeomAbs_Line;
-
-    gp_Pnt2d P2d(U,V);
   
-    Standard_Real Signe = L.Direction().Dot(Dv);
-    Signe = (Signe > 0.) ? 1. : -1.;
-    gp_Dir2d D2d(0., Signe);
+    const Standard_Real aSign = Sign(1.0, L.Direction().Dot(Dv));
+    gp_Pnt2d P2d(U, V - aDeltaV*aSign);
+    gp_Dir2d D2d(0., aSign);
   
     myLin = gp_Lin2d( P2d, D2d);
 
     isDone = Standard_True;
-  }
-    
+  }    
 }
 
 
diff --git a/src/Standard/Standard_Real.cxx b/src/Standard/Standard_Real.cxx
index 0c9733485a..b587af4f82 100644
--- a/src/Standard/Standard_Real.cxx
+++ b/src/Standard/Standard_Real.cxx
@@ -113,11 +113,9 @@ Standard_Real ATan2 (const Standard_Real Value, const Standard_Real Other)
 
 //-------------------------------------------------------------------
 // Sign : Returns |a| if B >= 0; -|a| if b < 0.
-//             from x in the direction y
 //-------------------------------------------------------------------
 Standard_Real Sign(const Standard_Real a, const Standard_Real b)
 {
-  //==== We use the function "nextafter()" fom library "math.h" ==============
   if (b >= 0.0) {
     return Abs(a);
   } else {
diff --git a/src/Standard/Standard_Real.hxx b/src/Standard/Standard_Real.hxx
index 84e84e0832..9beb501c32 100644
--- a/src/Standard/Standard_Real.hxx
+++ b/src/Standard/Standard_Real.hxx
@@ -37,7 +37,10 @@ __Standard_API Standard_Real    ACosApprox  (const Standard_Real );
 __Standard_API Standard_Real    ASin        (const Standard_Real );
 __Standard_API Standard_Real    ATan2       (const Standard_Real , const Standard_Real );
 __Standard_API Standard_Real    NextAfter   (const Standard_Real , const Standard_Real );
-__Standard_API Standard_Real    Sign        (const Standard_Real , const Standard_Real );
+
+//! Returns |a| if b >= 0; -|a| if b < 0.
+__Standard_API Standard_Real    Sign(const Standard_Real a, const Standard_Real b);
+
 __Standard_API Standard_Real    ATanh       (const Standard_Real );
 __Standard_API Standard_Real    ACosh       (const Standard_Real );
 __Standard_API Standard_Real    Sinh       (const Standard_Real );
diff --git a/tests/bugs/modalg_6/bug28054_1 b/tests/bugs/modalg_6/bug28054_1
new file mode 100644
index 0000000000..e024183e83
--- /dev/null
+++ b/tests/bugs/modalg_6/bug28054_1
@@ -0,0 +1,33 @@
+puts "========"
+puts "OCC28054"
+puts "========"
+puts ""
+#################################################
+# Regression: Class BRepProj_Projection gives invalid result after projection edge based on the line on the conical surface
+#################################################
+
+set Tol 1.0e-7
+
+dsetsignal 1
+
+restore [locate_data_file bug28054_FaceProj.brep] f1
+restore [locate_data_file bug28054_EdgeProj.brep] e1
+
+set ProjList [prj r e1 f1 0 0 1]
+
+if { [llength $ProjList] < 1 } {
+  puts "Error: no projections are found"
+}
+
+foreach wir $ProjList {
+  set EdgeList [explode $wir e]
+  foreach ed $EdgeList {
+    set dist 1.0e+100
+    regexp {Max Distance = +([-0-9.+eE]+)} [xdistef $ed f1] full dist
+    if { $dist > $Tol } {
+      puts "Error in projection. 3D and 2D curves of edge $ed are not same-parameter"
+    } else {
+      puts "OK: Max Distance is less than $Tol"
+    }
+  }
+}
\ No newline at end of file
diff --git a/tests/bugs/modalg_6/bug28054_2 b/tests/bugs/modalg_6/bug28054_2
new file mode 100644
index 0000000000..89958f9bb9
--- /dev/null
+++ b/tests/bugs/modalg_6/bug28054_2
@@ -0,0 +1,60 @@
+puts "========"
+puts "OCC28054"
+puts "========"
+puts ""
+#################################################
+# Regression: Class BRepProj_Projection gives invalid result after
+# projection edge based on the line on the conical surface
+#################################################
+
+set Tol 1.0e-7
+
+dsetsignal 1
+
+cone c 0 0 0 45 0
+trimv c1 c 5 10
+trimv c2 c -10 -5
+mkface f1 c1
+mkface f2 c2
+line l1 0 0 0 1 0 1
+line l2 0 0 0 0 -1 -1
+trim l1 l1 -100 100
+trim l2 l2 -100 100
+mkedge e1 l1
+mkedge e2 l2
+
+# Rotate f1 around e1 by the angle 32 degree
+copy f1 f3
+rotate f3 7 0 7 1 0 1 32
+
+# Rotate f2 around e2 by the angle 81 degree
+copy f2 f4
+rotate f4 0 -6 -6 0 -1 -1 81
+
+for { set i 1 } { $i <= 2 } { incr i } {
+  for { set j 1 } { $j <= 4 } { incr j } {
+    if { $i == 1 && $j == 4 } continue;
+    if { $i == 2 && $j == 3 } continue;
+    
+    puts ""
+    puts "Check e${i} and f${j}"
+
+    set ProjList [prj r e${i} f${j} 0 0 1]
+    if { [llength $ProjList] < 1 } {
+      puts "Error: no projections are found"
+    }
+    
+    foreach wir $ProjList {
+      set EdgeList [explode $wir e]
+      foreach ed $EdgeList {
+        set dist 1.0e+100
+        regexp {Max Distance = +([-0-9.+eE]+)} [xdistef $ed f${j}] full dist
+        if { $dist > $Tol } {
+          puts "Error in projection. 3D and 2D curves of edge $ed are not same-parameter"
+        } else {
+          puts "OK: Max Distance is less than $Tol"
+        }
+      }
+    }    
+  }
+}