alpha blending problem

Hi ppl i have problem with alpha blending.. i succesfully blend bitmap.bmp and bitmapalpha.bmp for the first time when it is drawed... but every other time i call my list Tree or any other it doesn''t blend correctly..Plz if anyone can help here is the code i use... GLvoid BuildLists() { Tree=glGenLists(2); glNewList(Tree, GL_COMPILE); glBindTexture(GL_TEXTURE_2D, texture[3]); glBegin(GL_QUADS); // Start Drawing A Textured Quad glTexCoord2f(0.0f, 0.0f); glVertex3f(-0.2f, -0.2f, 0.0f); // Bottom Left glTexCoord2f(1.0f, 0.0f); glVertex3f( 0.2f, -0.2f, 0.0f); // Bottom Right glTexCoord2f(1.0f, 1.0f); glVertex3f( 0.2f, 0.2f, 0.0f); // Top Right glTexCoord2f(0.0f, 1.0f); glVertex3f(-0.2f, 0.2f, 0.0f); // Top Left glEnd(); glBlendFunc(GL_ONE, GL_ONE); glBindTexture(GL_TEXTURE_2D, texture[4]); glBegin(GL_QUADS); // Start Drawing A Textured Quad glTexCoord2f(0.0f, 0.0f); glVertex3f(-0.2f, -0.2f, 0.0f); // Bottom Left glTexCoord2f(1.0f, 0.0f); glVertex3f( 0.2f, -0.2f, 0.0f); // Bottom Right glTexCoord2f(1.0f, 1.0f); glVertex3f( 0.2f, 0.2f, 0.0f); // Top Right glTexCoord2f(0.0f, 1.0f); glVertex3f(-0.2f, 0.2f, 0.0f); // Top Left glEnd(); glEndList(); } int DrawGLScene(GLvoid) // Here''s Where We Do All The Drawing { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glBlendFunc(GL_DST_COLOR,GL_ZERO); // Blend Screen Color With Zero (Black) glEnable(GL_BLEND); // Enable Blending glDisable(GL_DEPTH_TEST); // Disable Depth Testing glLoadIdentity(); glTranslatef(0.5f,0.15f,-2.0f); glCallList(Tree); glLoadIdentity(); glTranslatef(-0.5f,0.7f,-2.0f); glCallList(Tree); glEnable(GL_DEPTH_TEST); // Enable Depth Testing glDisable(GL_BLEND); }