Continuity mistake: Toward the end of the movie, when Bernie is going to fight Jack, Jack's hands are on his hips then in the next shot they are down.
Continuity mistake: After Bernie accidentally kicks Greg's face and then the argument starts out front by the RV, the sun is shining when either Jack is shown and/or the Fockers and Pam from their backsides but every time the Fockers and Pam's faces are shown, there is no sun on them at all (through from that angle it should be shining on their faces).
Continuity mistake: The empty rum bottle that was placed on the table in the room during the families arguing disappears after the Fockers walk out of the room.
Visible crew/equipment: When Jack drives away from the Fockers' house the filming crew's white pop-up tent is reflected on the RV.
Continuity mistake: After Jack leaves the whole group Greg phones him and then puts the phone on the table. Its position changes between shots.
Continuity mistake: When Bernard lies in front of the RV there's a sunny spot a meter away from his head which becomes shadowy in the close-up. This swaps back and forth.
Continuity mistake: From a wide angle Greg is covering his bloody nose with the palm of his hand when Roz hugs him. A shot later, in the close-up, he covers it with the side of his hand. Then there's a different angle, and afterwards it cuts back to the first wide angle with the initial palm-of-the-hand position.
Continuity mistake: Before Bernard leg-kicks Greg, Jack's arms swap from crossed to down by his side between shots with no time to lower them.
Audio problem: When Jack tells Bernard from a side angle "you will force me to engage you" his jaw is not moving.
Continuity mistake: When Bernard tells Jack that he's gonna kick his ass, Bernard's position changes between shots: sometimes he has his back to the road in front of the RV, others to a flower bed sideways to the RV.
Continuity mistake: When Greg is giving his speech-of-truth at the party he extends his right arm and points at Dina. From the opposite angle his arm is lowered.
Continuity mistake: At the party Bernard proposes a toast to his son and raises his left arm. From the opposite angle his arm is lowered.
Continuity mistake: After sticking the needle in Greg's neck Jack extends his left arm and puts some cotton on the wound. A shot later his arm is suddenly lowered.
Continuity mistake: The position of the sodium filled needle on Greg's neck changes between shots: Sometimes close to the ear, others way below.
Continuity mistake: At the party, before Dina strokes Jack's ears her left hand is either on his chest or not depending on the shot.
Continuity mistake: During Roz's massage, when she says "unleash the beast", in the close-up shot her hand disappears from Jack's shoulder.
Continuity mistake: During the massage scene, after Roz takes Jack's shirt off he raises his head. In the close-up it's pressed against the pillow, then angle cuts back to his head raised which he then lowers.
Continuity mistake: After the cat opens Jack's playpen the toys in front appear/disappear randomly between shots. Also the opening of the door changes when Greg brings the rum.
Continuity mistake: When Jack sees the glue bottle it turns 180° between shots, check the position of the label. One could argue that both sides have a label, but a shot later the kid is grabbing the glue and there's no label on the side facing the camera.
Continuity mistake: When Jack is about to grab the remote control, check the pattern on the carpet: The position of the remote changes.
Answer: Muskrat is a "code word" they use to remind Jack to keep his temper under control.
Myridon